So, when it comes to CP victories if any kind, it seems the most they can take from Russia are the non Russian areas of the western areas of the empire. But, the rest of Russia is still pretty big and fill of resources and it's hard to imagine Russia, even so weekend, becoming submissive to Germany or any other country(China?). I mean, even today, Russia stands pretty much on it's own as a relatively powerful nation that can't really be described as being submissive to any nation.
So, not counting any Nazi plans of any sort, what's the weakest point Russia could be pushed into with a pod of 1900. And by weak, I mean that it's basically a puppet/vassal state. Is such a thing even possible?