This is probably a less popular opinion, but you got lucky this time because you warned her. You know the dog is aggressive and you are liable if it happens to another pet without warning. It may be time to consider some specialized training for the dog, or investing in some equipment, indoor and outdoor gates (if you don’t have them already), warning signs, etc etc etc so you can try to prevent future attacks. I’m also a dog owner of an 80 lb hound who likes to chase small game, and I sympathize with your situation.

But... there’s a million scenarios where leaving a door cracked open or some accidental opportunity comes up for the dog and you’re in much deeper shit. You already know this, so I’ll save any other lecturing, but just because you warned this person this time doesn’t mean you have solved the problem for the future.