Property Manager Beware

I manage property in Arkansas.  The other day one of my tenants purchased a home and was attempting every means possible to get out of their lease. They decided the rental was in need of some repairs and said they found a spot of , deadly mold under the kitchen sink. In short, I would not let them out of their lease. A few days letter I received a letter from their attorney stating they had filed a law suit against me, the property manager. Has anyone had experience with this and how did you handle the situation?