It is not known what transpired before the tape started rolling. The cop sounds upset on the tape, so I say no to the hit theory.
The new clues given in the link raises many, many questions.
Here’s a scenario:
The guy robs a store at gunpoint. He gets pulled over and the GF notices that the cop sees the gun and announces the guy has a CCW permit to explain the gun. The guy goes for the gun and gets capped.