Ah Ukraine/Russia (I happen to be born there albeit being a US Citizen), Skilled Labor Costs are low, and most of the younger generation a english fluent, at least internet english fluent.
I do web development projects with people from there, the salary level of a clued IT person is abysmally low compared to the USA, especially if outside of places like Kiev and Moscow where the cost of living is definately closer to western europe, emea, americas etc.
If a vanity website project with a full backend can be had from Yekaterinburg or Lviev for in or around $1000 USD and the most elite developers in Major cities have rates of under $30-$40 USD per hour (which translates well into their local currency and a good lifestyle) then this is why the hiring is primarily done in those locales.
I also suspect the secondary reason may be that the lead development/company culture and management may be communicating in Russian (a lot of Isralies speak it - maybe even the company founders) so it may be that guidlines and edicts for future dev may be typed out in Russian - and so knowing it is the only way to onboard less senior staff.
P.S. This also explains why the game has Russian enabled and I thought to myself what an odd choice of a language to make sure is supported in the game... This explains a whole ton, since I'm fluent in Russian, I'll try that approach to escalating issues, maybe get more milage.