You can never be sure, we were sure afghan army will hold and we were sure Ukraine wouldn't last long, and the opposite happaned.

The logic is that this war is as close as it gets to 0% approval, and many soldiers arent happy aboit either. If they had a way to avoid killing their 'slavic brothers' that does not lead to being stuck in a gulag, a significan portion would take it. I am not sure how much money theid need, but compared to cost of a war, this is cheap. Kremlim would be bleeding manpower.