The Red Army was pretty tough in WWII. I don't see why he'd want to.
The article suggests that at least one area of interest was for heavy physical labor such as building railways. Although the gulags were full of poor souls whom he had no problems with working to death, perhaps he thought that the apes would be faster, cheaper to house and feed or more efficient?
I hope that the 'secret documents' referred to in the article will become public one day, as they may provide more clues.
Collectively it was ... individually they weren't. Kinda like the Sherman tank versus a Panzer IV. We won the tank battles because we swarmed them.