The slam dunk for this will be found with the autopsy report, and it will be based on how the bullet went through Martin’s body. The angle of the bullet track will show whether Martin was standing upright, was on top of Zimmerman as he described, or otherwise.
If he was straddling Zimmerman, with Zimmerman firing up, the bullet track is going to be very obvious and almost impossible to reproduce were they both, or even if one or the other were standing up.
And I don't see your take..at all.
The muzzle of the pistol could have been in angles we can't even imagine.
Fwiw-