He could not see what they guys wife was doing he had a face full of popcorn. He was reacting to the physical assault. His wife's perspective, view of the situation was unobscured by popcorn so she did have a different assessment of the situation than he did. She saw what he could not see because he had a face full of popcorn. He reacted on what he knew and saw. There is not time to have a discussion in a reactionary "shoot no shoot" situation.
This will all come down to if he can convince a judge or jury that he was in fear of great and grievous bodily harm or death at that split second in time. None of this will be about what other people with better vision of the situation thought. He did not have that view or that knowledge at that time.
I don't put any significance on his statement later. I've been around a lot of cops and they always make smart-ass cynical remarks. That is how they deal with bad situations no matter if they are involved or not. That is just a cop being a cop.
It was not a physical assault.
There was no physical contact between them as both the video and the witnesses testify to and as acknowledged by the police and the prosecutor -- and his lawyer.