Hello everyone, posting for the first time here. Thanks for sharing such a trove of information. I'm more interested in the logical deduction in this case, so here's my two cents.
IMO, I will assume that GZ will definitely offer a version of events most advantageous to his defense, and TM is dead, so if I were a member of the jury, unless substantiated by facts, GZ's account will be disregarded to place both sides on an equal footing.
So one male is not only 40+ lbs heavier but 12 years older than the other. He was lethally armed with a loaded pistol while the younger man was unarmed. He had been watching and following the latter, in full command of his senses, packed, comfortable about his "turf" and knowing what he was doing when he targeted TM. TM was being followed, and most likely afraid as GZ's identity, intentions, hostility, armed readiness, etc. were completely unknown, and he was a guest in this neighborhood, a stranger.
Clearly one party was far more dominant and in control of the situation, ready to act against someone he already believed to be a "punk" who might get away, trained in MMA, ready to use lethal force if necessary. The other ran away from an uncertain and possibly dangerous situation, unarmed and fearful. One predator, the other prey, it makes sense.
Following a 2-minute altercation, the weaker male died of a fatal gunshot wound at the hands of the dominant male. Based on Occam's Razor, GZ being the aggressor makes the most sense. The test of the pudding is in the tasting, etc...
The Defense is asking us to suspend logic and reason for the 2 minutes to consider an opposite scenario, that despite all of the above conditions, being younger, lighter, thinner, unarmed, more fearful, less experienced in fighting, etc., TM was suddenly able to turn the tables round and potentially deliver lethal injury to GZ. This sudden ability for all of 2 minutes is only supported by GZ's account, as none of GZ's injuries would qualify as life-threatening, and no available medical documentation supports this version of great bodily harm done to GZ.
At the end of these 2 minutes, the events once again follow the earlier logical trajectory - the prey, the younger, weaker, unarmed male is stone-cold dead.
Believing GZ's account for those 2 minutes therefore takes jumping through several hoops. Again, we must remind ourselves that GZ's account is the basis for his defense, therefore should not be given carte blanche.
IMHO, Occam's razor applies, until strong, credible, admissible evidence shows otherwise.