Given the fact, that the Soviets will land on Moon in the "Earthrise", it's pretty obvious that they will try(and succed) to hijack, or rather, reclaim their rockets. It's curious however, how can they still spare elite taskforce to fly to the Moon, if the alliance with Chinese is broken, and half of their army is brainwashed?
They're not really low on manpower like the allied nations are. In the stolen tech previews from youtube, foehn forces could be seen attacking epsilon and purple soviet forces, which could mean that they were mind controlled, and if they were, it probably wasn't just a handful of survivors but an army, implying on A: Epsilon wins (which we all assume even though the devs don't confirm it) and B: There were many soviet forces left when they lost, which is reasonable given that China is the most populous contry in the world and they're using powerhouse methods, so there should be A LOT of manpower avaible there, LC is formed by the considerably populated Latin America, and Russia is, well, big. And mostly under epsilon control already.