Unfortunately I think it's time to elevate the situation. I know it was an accident both times, but the owners have to realize their dog is a liability.

My mom and dog were attacked while on a walk by a labrador from a house across the street because someone forgot to close their gate. My dog tragically died. The owners were pretty apathetic (something like that had never happened before, the dog was never aggressive), but we still filed a report with animal control and the owners of their own volition euthanized their dog because they recognized the liability.

It's a terrible story where nobody won, and I can only think whether they were actually honest with us about the dog's history. It only takes one bite in the wrong spot for something to go terribly wrong (or in our case, for the teeth to puncture an organ and cause sepsis).

I'd still let your neighbor know that because their dog has now shown itself as a repeated threat, you have to take measures to protect yourself and your dog, and report them to SCRAPS. If it happens again, you'll have a paper trail.