@Greystone0 AirBnB's website caps animals, i.e. PETS at 5 (five). They do not state anywhere how many service animals must be accepted.
How many animals do you accept at your rental? It sounds as if you have a guest who has claimed that all of her animals are Service Animals, when in fact, they are probably well-trained animals who provide support to persons who are in need of a loving animal during their therapy sessions with a doctor. My sister has a friend who has multiple therapy animals that she takes to hospital and nursing homes.
On my listing I state that I will accept UP TO 2 animals. I have never had a guest bring more than ONE "service animal", and never in conjunction with other non-service animals.