This looks like a justified self-defense shooting to me.
One thing that should stick in people's minds after the travesty that was the Daniel Perry conviction is that it's not reasonable nor sensible to demand that people wait until a gun is aimed before acting in self-defense. Bullets travel really freaking fast. It only takes a small fraction of a second for the pointing of a gun to result in death.
Mr. Dasaur made the decision to present himself as an imminent deadly force threat.