This isn't "evidence" per se, but I have been wondering where George was attacked in relation to his SUV. If it was near his vehicle, then that shows that George was returning to his car and not continuing to follow Martin.
As George was talking to the dispatcher, he was trying to tell her where he was located (Point A). That fight was between that spot and his car. He was definitely heading toward car and had lost sight of TM. BUT the fight was closer to A then to his car.
Some suspect that John (as in John Doe) may have seen more than he told the media interviewer. He discribed each of the individual, who was yelling, how he told both he was going to call 911 ( His call was NOT one of the tapes released by the city).