The russians figured out that coming from all sides will seal the SPW 521/1 in place for the kill in the following turn. The Germans are dismounted. The halftrack is pointing in the wrong direction. And yeah, the 3-3-7 have MOL.
Strangely, I can't recall of any rules which makes it dangerous to engage with fire when there is a friendly unit right on the other side of the target. Any such thing?
What course of action is the most likely to save as many Germans as possible? If and only if they are almost certain to die, how would you make the russian pay the highest price for their kill?