The Russian civil war was a massive conflict where the Red Army consisted of several million people. A few divisions would not be enough to break the Soviets, and the entente powers of OTL showed very little interest in putting what was sufficient to put the Soviets down due to lack of will following WW1.Post 1918 the Allies sent soldiers pretty much everywhere to fight. This is more of a mop up action, not reenacting the Battle at the Somme. A few properly supplied and equipped divisions is all it would need to turn the tables in the Russian civilwar. OTL Germany fought communists as well as local independence movements in the East after the war. The Soviet forces were not what they were to be in 1944, not even what they were in 39.