Going from the
transcript TheL8Elvis posted above it's hard to make sense of that given the location of the incident if Z was just waiting by his vehicle to meet with police and was attacked by Trayvon. If the kid was "running" it certainly doesn't sound like later he came back and attacked Z, that is unless Z pursued T after the call.
After this exchange comes the, "are you following him" comment.
I can't see any way to make that exchange match up with 'lost sight of T and was going back to his vehicle' when T supposedly returned to attack Z.
On the phone to the girlfriend she says she heard T ask Z why was Z following him, and within minutes T was dead. The only way that fits with Z's 911 call is if Z pursued T after hanging up with 911. Keep in mind the location of the shooting was on a sidewalk between rows of back facing condos on both sides, well away from where any vehicle could be parked.
Why would T run away only to come back and attack Z? Does that fit any logical senario at all?