Over the last eight years, the quartet all separately relocated from South Africa to New Zealand. While Wagner's story is well known, the other three are also hoping to make an impact on the cricket scene - Viljoen following in Wagner's footsteps, and Walter and Roux as coaches.
The last two began their careers at a similar time at the University of Pretoria, and while Walter went on to work as South Africa's fitness and fielding coach before taking up a head coaching role at the Titans' franchise, Roux was in charge of Netherlands. Things were going well for both of them - Walter had won three trophies in three seasons and was eyeing a clean sweep of the domestic competitions in his fourth summer - while Roux had been to two World Cups and was hoping to help the Dutch qualify for another, but both felt the need to develop themselves a little further. Each unaware of the other's interest in Otago, they both applied for the head coaching job, which Walter was offered on a two-year deal.
Then, he faced a "massive decision", to leave South Africa just as big success beckoned. "We put a lot of work into developing a team culture, and from a personal aspiration, I would have loved to do the triple. I felt the team we put together was good enough to do that, but that would have been a trophy-in-the-cabinet aspiration, not a personal-growth aspiration," Walter said during the Dunedin Test.
Partly, the lack of opportunity higher up in the South African set-up - at the time Walter did not know Russel Domingo's contract as national coach would come up for renewal - played a role in him choosing New Zealand.
"It's the responsibility of a proper leader to leave his environment in a place where it can continue to be successful when he is gone, not to take success with him," he said.
"I decided to make a move purely for the interests in developing myself as a coach. I felt from a South African set-up, I had learnt what I needed to learn at franchise level, and we had done pretty well as a team. I thought it was a nice time to make a move and go somewhere and grow, immerse myself in a totally different cricket environment and see if I could be successful."
Roux was given the assistant role, and though it was a step down from what he hoped for, uncertainty in the Netherlands job forced his hand. "We didn't know what was really lying ahead with Associate cricket, so I thought it was the right time to look for something else," he said.
The move brought its challenges. Walter left his wife and then four-month old son in South Africa in September last, knowing they would only be able to join him in June this year. Roux and his partner, who holds a Masters in Public Health, moved from Amsterdam, where work opportunities for her were plentiful, to Dunedin, where they are not. Both men, who are keen runners and enjoy the outdoors, decided the upsides would be worth it.
"Amsterdam is a great, vibrant city, and Dunedin is probably not so much that, but in Holland you don't easily get to nature. Here you can walk out of your door and you're ten minutes away from a beautiful forest or beach or trail," Roux said.
Of course, they didn't relocate solely for the landscape. Soon they had to get on with the job of lifting an Otago team that had not won a trophy in three seasons.
The first step was to familiarise themselves with a group of players they barely knew, and to get them to buy into a different and perhaps more intense coaching style. "We do it our way because that's the way we trust and it's based on good work ethic," Walter said. "A lot of it has been quite new for these guys, and anything new is exciting.
"I joined the Titans knowing every single player in the team, having worked with them in some way at some point. It was a lot easier to start there than it was here where I knew two people - Wags and Christi."
Viljoen, who did not brave the Dunedin weather to make an appearance at our interview, came to New Zealand via Namibia. After his time at the University of Pretoria Academy, where he was coached by Walter and Roux, Viljoen hopped across the border, but like Roux, the frustrations of Associate cricket forced him to head back to South Africa.
This is his second year in New Zealand and he has to spend another two before he can qualify, which takes him to 2019. By then he will be 31. Walter confirmed a Black Cap is very much in his sights. "I haven't met many guys who don't have that idea in mind - to come here and qualify," Walter said.
Naturally, that raises the question of how many more South African players will join the exodus - which reached tipping point when eight recent Test caps signed Kolpak deals earlier this year. Walter has a few theories.
"It's very obvious that there is a big influx of young South African cricketers into New Zealand cricket. I think you're seeing the top level signing Kolpak, and then the younger cricketers are leaving to come here," he said. "I don't know whether they feel there is a greater opportunity to play or whether they feel they are being marginalised in South Africa, but we must be careful to think it's just [happening] here. If you look at Netherlands, Canada, a lot of Pakistani guys playing there. We think its unique but it's not."
To those looking for opportunity, Walter has a few warnings about the perception that the pathway is easier in New Zealand. "The current cricket set-up in SA is really strong. Corrie [van Zyl] is doing a great job with the structures and processes in place, and the playing opportunities that are available to players now. If you look at the SA A side program, it's immense.
"There was hardly any New Zealand A cricket this last year, and there is no official competition barring a week's competition for the level below franchise cricket, so there's no B side cricket, as we would say in South Africa. That's the biggest standout difference. As much as there is often a complaint about playing opportunities in South Africa, there is much more than there is maybe here."
Roux said that it is "quite tough for the guys on the fringe of the franchise team to stay motivated and involved", which has presented him and Walter with another hurdle. "We have to set up our programme to work around that, and also bring to the foreground to the guys who work in administration here that we need a bit of action in that second tier," Roux.
Without the development of a second tier, the gulf between franchise players the rest will continue to grow. "We only contract 15 players but in a season we will use around 19, and you see the biggest difference there," Walter said. "Because they don't get to play a lot, you can see the difference in the quality. The depth is not as good as it in South Africa. It's our biggest focus to create opportunities for those guys."
In an injury-hit season of the sort Otago have had, the consequences of a shallow system are obvious. Their results have not improved as much as Walter and Roux would have liked. They finished at the bottom of the Ford Trophy and Super Smash points tables and lie fifth on the Plunket Shield table with two matches to play.
But the pair is optimistic things will change and has made winning the first-class competition the main goal for their second season in charge. "We haven't done as well as we would have liked but its still early days," Walter said. "We want to win the four-day campaign.
"I've really enjoyed the guys and their excitement to new ideas and to learn and grow from us. We've got different experiences to their previous coaches. We're able to pass on different stories and different experiences of things they haven't seen before."
After next season, when their contracts come up for renewal, they hope to have something to show for that.
Walter is not planning on applying for Domingo's job, which has been advertised and will be filled after South Africa's tour to England in August, just yet, and isn't giving away whether his eye is on Mike Hesson's after the 2019 World Cup.
"If there was some interest from Cricket South Africa, I would consider it, but for now, we want to create something special here," he said. "I see huge opportunity in New Zealand cricket in terms of where it can go to. There's a lot of areas where they can grow, and that's exciting because they want to. It gives us an opportunity to build something. If that leads to a national job at some point, that would be great.
Roux, only 35, feels he has enough time to get experience on the domestic circuit before aiming for the step up. "At the last World Cup I had a look around to some of the coaches and I realised I was the youngest by 14 years. For me to have an experience of two World Cups under the belt at my age, it's a huge privilege. Right now I am helping Rob build our dream. We want to be as successful as we can here - you can't think too far ahead, but obviously internationally is where you want to be," he said.
He would even consider going back to an Associate, maybe even back to Netherlands, if the climate is right. "After a year or two, the real test of Dutch cricket is going to come, when the older statesmen start moving on. Hopefully by then the youngsters have stepped up," Roux said. "My concern was that they may not have the depth to keep renewing themselves as the generations move on. Cricket is not at the forefront of their minds, so the kids who are taking up cricket are not necessarily your best athletes. But Associate cricket as a whole is improving and I am looking forward to seeing them do well in future."
For now, he is happy to immerse himself in the country he has moved to, from the heat of Pretoria, to a place not far from the South Pole; from a place where results came a little easier to one where the work is tougher but the rewards may be greater.
"When you fly from one city to the next, you are just absorbed by what you see out of the window," Walter said. "For now it's about seeing everything there is to see here and experiencing what there is to experience here. As long as we keep in the forefront of our mind this is not just about the cricket - it's part of a greater life experience."