Sorry, i am not a pet owner so I do not have any strong opinions about controlling the pet. It sounds to me like you are trying your best and doing a reasonable job.
Your neighbor is a whackadoo. If you have your car parked outside, SOMETHING is going to walk on it. If it is not somebody's cat, it will be a squirrel, or a possum, or a racoon. Who do you call to complain about that?
Same thing about the burrowing. Does she not realize that cats are not burrowing animals? They do not have a digging instinct like dogs. If your cat was "burrowing" under her house, it was chasing a mouse or a chipmunk, which was the real cause of the damage. Who is she going to complain to about the rodents?
Whackadoo. Ignore her.