I've been pretty familiar with the case. I thought thats what the photos were all about, proving that Zimmerman had a split skull and needed stitches.
If Zimmerman was really pinned down, then he would not have been able to draw a gun and shoot. Logistics people!
Anyways, I can't really feel bad for the guy after he sold his ordinary handgun for 250 k, years later. I read that on multiple sources.