Technically, you shouldn't know it was friendly fire, but that's a minor quibble.
Your action looks plenty logical to me, though it may take some work to get unburied. You may be better off going the other way down the tunnel and popping out another bunker- if so, 3 is a decent choice since they have heavy numbers headed their way.
I don't think they're going to dig out the bunker- just assume you're dead and go on.
Well, I IC know that the other side doesn't have artillery and we got fucked with an artillery shell. I'll do what you suggested, though, as I think Steve announced that the group attacking F turned toward the auroara.
My turn'll be edited in several (read 3-5) hours.