An option may present, given Drysdale's pedigree, to follow athletes like Val Adams, Nick Willis, Lauren Boyle and Andrea Hewitt who effectively work outside their respective national programmes.
Rowing NZ chief executive Simon Peterson said a resolution is still sought.
"We had a contract in place with Dick until Rio, so we were surprised by his tutelage of the Chinese athletes. We put an option to him to continue with his New Zealand crews, provided he sought a release from the Chinese. He went with the Chinese."
In response to suggestions it was common practice to work with overseas rowers, Peterson responded: "It's not right when one of the top coaches in the world is on your payroll. It's a bit different when other athletes come for a short period and it's framed up beforehand. We were blindsided."
Tonks described the athletes as "provincial level" and keen on contesting the 2017 China national games. However, two of the four, Dong Tianfeng and Tin Bian, were part of China's lightweight men's quad who won bronze in the non-Olympic discipline at the 2014 world championships.
A year on, the duo were third in the D final (21st overall) in the men's lightweight double scull. New Zealanders Peter Taylor and Hayden Cohen were 13th.
"They've got a coach with them as well," Peterson said. "We've done our homework. They're listed in the results sheets when our athletes competed [at the world championships] in France.
"The best outcome is to get what the athletes want, and that is to be coached by Dick through to Rio."
High Performance Sport New Zealand have invested $5.3 million of taxpayer money in rowing for the final year of the Olympic cycle.
Chief executive Alex Baumann released a brief statement: "Rowing NZ has kept me informed of the situation, but it is an operational matter for them to resolve. I retain full confidence in rowing's wider high performance programme, and their ability to deliver medals for New Zealand at the Rio Olympics."
For Tonks, the matter seems simplest, even if he risks a self-imposed divorce from his athletes. His coaching mantra comes down to three words which have served him for his coaching lifetime: "miles make champions".
Some athletes love him, some dislike him, most respect him, but the incumbents owe their government-funded livelihoods to the platform Tonks' athletes built over previous generations. He is New Zealand's most successful Olympic coach, overseeing five gold and one bronze medal across the last four Games.
You only had to witness the compassion he held for Bourke, an incumbent women's double world champion struggling in the single at this year's Lucerne World Cup, to understand there is empathy beyond the gruffness.
"I was terrified to talk to him but realised it's just that he takes his job seriously," Bourke said last year. "He has great intuition for his athletes. If you are willing to put the time in, he will too."