[Ts4EVER]

Well that is 23 armored vehicles vs 14 of yours (in the core force), with your only artillery support being two mortar squads. Your core force is worth around 1500 points, give or take. The German force comes out at around 2500 points and they are defending and dug in. Now maybe it is not "impossible", maybe there is a way it can be done, but as someone who has some experience playing this game and making scenarios for it, I would say it is at the very least quite unfair.
And the fact that the standalone version of the very same campaign mission gives the Russian player a significantly bigger force leads me to believe that there was some kind of oversight here. Maybe the standalone one was made first, tested and then added to the campaign, but he forgot to set some of the forces to aux?