bed bug disaster

My sister and her friend just got bed bugs from a dirty bed at the host´s apartment. they had evidence (doctor´s approval, photos), that they have not had them before. they were thrown on the street after the host told them THEY brought the bugs – also they had no more money left because the airbnb money they already paid in advance takes a while to get back to their accounts. after hours of exhausting phone calls they finally got 500$ from airbnb to stay at a hotel and a few options for new apartments (btw they were in treatment already and the bugs are gone). after booking another one after a week airbnb called the host to throw them out again because they´re too dangerous. funny thing is: the apartment where they got them from is available again!