Since this thread has been well necrod, can you explain further, please?
Actually, I had another mission in mind. The ToW co-op on the big open 4v4 multiplayer map with fuel on the South "Island" and mid. That one nowadays have ramped up difficulty as I understand it. I asked one who had done it on general difficulty before, how he did it, and he said that was pre-patch and that he can't do it anymore. Not with a human partner anyway. The mission features KV-1's after five minutes and swarming infantry.
Kharkov Pursuit is very difficult as well but but maybe doable. I haven't put in enough attempts yet to be sure.