You truly do not understand the words vigilante, or aggressor.Yes there is, you aren't allowed to be a vigilante. It is one thing to happen upon a crime and acting to help, but it is another to illegally arm yourself and drive in from out of state and patrol as if you're the law.
Self defense laws are for the innocent bystander, not for the vigilante. I know you guys get all a twitter thinking about dirty harry wannabes blasting libtards until women are scared to vote and black people get back in their sheds, but people aren't allowed to run around as Captain Incel shooting people. That's the police's job....for now.
He wasn't acting in self defense no more than anyone who walks up to Mike Tyson and punches him in the face then screams self defense when he whoops your ass and you want to shoot him.