Hi and bless you for caring enough to help this sweet dog in need. I've read your initial post a few times and something about those people claiming the dog is theirs just doesn't feel right.

Morally, I believe you did the right thing getting her to the vet and trying to find her owner. I'll research the animal laws of your state but if you're concerned about your legal responsibility, you might want to consider contacting legal aid or a local law clinic (many law schools have them) for an opinion. You might even be able to get legal answers from your vet or one of your animal shelters.