This is super useful, thank you! I really appreciate the experienced insight. I figured that since I went in telling them to look for a specific issue which did turn out to be there, that it made sense no one noticed the issue they weren't looking for. & I've seen abscesses in cats only twice before, and in the one I spotted in advance I couldn't get the cat into an appointment before it ruptured--a 24 or 48 hour wait time, which gave me a good indication of how quickly they go from unnoticeable to already ruptured. It's comforting to know that that's also true for vets, and this isn't the case of anyone's oversight--just bad luck.

Ironically, we had just started to get really good handle on monitoring how Toby and August were interacting, how to anticipate him chasing her, how to trade up to a toy or other appropriate behavior ... but I guess the damage had already been done! Which sucks, but it still bodes well for no more bites in the future.