Did you know that if an off duty cop tries pulling you over (not in a police car) it is perfectly within your legal right to call 911 on your cell and get directions to the nearest police station, oor location where a marked squad car will be present. This is a safeguard to prevent people form buying lights for their car and stopping anyone.
Granted, a drunk NFLer wasn't about to use that option.
I think a lot of the situation will depend on at what point the offduty called it in. If he called 911 or radioed in, the moment he saw the drunk driver, and they just took a while to arrive, it looks like a police operation gone bad. If he didn't call anything in until after there was a man bleeding on the ground, following multiple confrontations and warning shots, then his ass needs to be off the job. It takes about 1 second to hit 911 on your cell, if for nothing else than to put a recording of the events on public record.