Didn't watch the stream live, but looked it up now. NPC did fight back after two hits like they usually do, but yeah. Dropped a very wonky weapon. Not the weapon itself as I think that can drop from other enemies as well, and isn't named and can be used at low levels, but it had +8. Going by regular DS upgrade mechanics, I'd assume that is indeed broken for the area since that would require chunks and the likes to get it that high and I've only seen people get small shards in the first area. So not sure if that massive upgrade is intentional or if they did an oopsie when setting the + stats on it.
That said, he died repeatedly against every boss he tried after it. Damage was indeed high as it did 1h as much damage as Elajjaz did with a 2h that he found that wasn't upgraded. If someone like Elajjaz got that weapon that Azmon did, I'd assume he would walk all over the content in the first zone without much hassle.
Doesn't really matter for me though. I never kill talking NPCs in first runs. I want the lore and possible quest progressions more than an item.
For those wondering what the weapon was here are stats on it
For comparison, here is his regular +1 starting weapon