I can't prove this is Jimmy but I've not heard anyone doubt it yet, anyway on the left, newspaper or perhaps motorcade schedule in his right jacket pocket, no sign of a shoulder strap and none in Hughes either unless I'm mistakener(haven't checked I just don't remember seeing one).
Same pocket has something white near it in Towner.
The Sitzman being interviewed footage by the shelter was credited to Jimmy by Trask himself, why IDK but could be part guesswork, in that regard, I guess Mack let him view some under the counter stuff from time to time.
I also guess that what Sitzman's told the reporter or cop garnered Jimmy's attention and that of some girls nearby, that's what upset "Holt" again and off she went with Jimmy in tow.
Darnell wasn't shooting random scenes, he was doing reaction work, like with the Newman fist pounding, how long do you think Bill was hitting his fist on the ground? 5 seconds? Try it yourself, five hits seems about right, well, Jimmy caught it, that is a great point and shoot catch, that's what he was trained to do and waiting for, something, anything. 98% of his footage seems to be reaction shots. The one under the spotlight here has his DNA all over it. It's OJ at Bundy.