Like I said, mask or not you should be able to recognize a teen, especially your son. Dude was obviously fogged by adrenaline, and the rage of that gun in his pocket. He went over there knowing he was gone to shoot somebody and he did.
Bringing a gun to a gun fight affords one no extra protection. If someone points a gun at you, your dead. Ain't no Clint Eastwood movie shyt where you can get to your gun first and kill the robber. Which is why I woulda made it my business to get in get my neighbors out then call the police. No material possession is worth shooting or getting shot over.