stroo wrote:1. If you don't know, don't shoot.
2. This guy appeared to be doing what all the self defence teachers teach. After the assailant is stopped, scan for other threats. He may not have been using good muzzle discipline, but that is what he was doing. And as I read your statements here, you recognized that whether implicitly or explicitly.
Shooting here would have been a big mistake for you.
Either scram or take cover and - draw your firearm or at LEAST have the grip in hand ready to go. I don't think drawing yours discreetly is out of the question with another gun already being displayed. . . but there's no need or benefit from presenting it to the guy who is beyond red alert, in full fight-or-flight mode, and likely scared out of his wits.
You might even call out, "We saw what happened, the police are on the way" to try to ease his nerves a little.