BS. It is almost impossible to find a good renter allowing to rent to someone with a dog, let alone a cat. Most landlords have a NO PET policy.....understandable.
You have the upper hand here. Tell her to clean up her dogs crap or get the heck out.
If she is not cleaning up after her dog, which a responsible tenant would, then she is taking advantage of you.
Or, do it NGY’s way if you want to stay mad.