I've seen no reports that cops ordered everyone to stay where they are. In fact what I read is that the cops were attempting to clear folks out of the area.Maybe I'm misunderstanding the events that took place but he wasn't detained following a description of a shooter.
Shots were reported in an area/place--cops investigate said place and order everyone to stay where they are and one guy decides to make a break for it.
The notion that Bennett was the only guy "to make a break for it" is laughable. Shots are heard and everyone stays put except one guy? C'mon.