That about sums it up. Plenty of anecdotes about the Russian army raping its way to Berlin, but what was the result? How many half-Soviet babies popped out once the Allies triumphed? I'm unsure of how census data was taken back then, and whether said data would be complete enough to observe a trend such as this.
Edit: Simply put, what are the chances that a random male born in Germany today will have heritage that traces back to Russia/fmr USSR?
There were massive amounts of rapes, but only a very small percentage of those would have lead to pregnancies. Even then those babies would grow up as Germans, I don't see how there would be an ethnic shift?
BTW. next time you might want to ask questions like this with a more refined tone.