I can tell you my experience with a situation that occurred in which I had to respond to a medical emergency where I now work.
I was an EMT. My ptsd is related to that.
What I do for employment now, has nothing to do with the medical profession in any way. This is a deliberate choice on my part. Though I certainly have wondered how I would respond to a situation that forced me back into that role.
I'm going to mention first that I agree with
@EveHarrington 100% in that I also believe it is a individual thing, how one reacts to the kind of situations we fear most. More than that, I think it's probably individual to each specific situation. I don't think one can predict it. Ever.
That being said, here's what happened.
A coworker cut themselves with a box cutter knife. This was the worst injury of this type I have ever seen. He managed to sever his radial artery in a single incision, extending from the base of his thumb, ending just behind the curve of the wrist.
Ironically, he was teaching new hires how to safely use one of these knives. (I wish I was kidding. That was his last training course. Lol)
Fortunately, no.... miraculously. He managed to miss a very important tendon and nerve. All he needed was stitches and a few staples, then he made a complete recovery.
Anyways, the point...
I was the only one on staff that didn't run the other way. I took charge of the scene, got him stabilised and ready for transport when EMS arrived. I was surprised at how well I handled the whole thing. Though really I had no choice. No one else was calm, so I had to be.
Afterwards, I was a wreck. But while he was in my care, I handled it like I'd been doing it for years.
If anything like this happened again, I have no idea how I'll react to it. I don't feel any more confident in myself now than I did before that. Maybe I'll freak out and run in a circle flapping my arms. I just don't know.
That was a situation that scared the shit out of me. That's how I handled it, but not how I thought I would handle it.
So, maybe your husband will surprise you and himself, should you have to face a violent mob.
Or maybe not. I don't think it can be predicted.
That's the best I can think to tell you. Probably not helpful, but there it is.