Should I reimburse for a 2nd dog during current sit if family is having me bring dog to board at kennel because she is damaging things in the home?

These people have not trained their 18 month old dog well and even though I am suppose to leave both dogs in the house, not crated for up to 4 hours 2 x per day... The younger dog chewed up my shirt part of the stairs, a plant and part of a dining chair today. I was only gone 2.5 hours the first time and she has large chew toys and similar to rawhide items to work with. the 2nd time I was gone for 3 hours closed every single door and thats when she went after stairs and dining chair. Client claims she has only chewed on a box or two once or twice recently and never does this stuff. She also said she was a great walker and even with my training lead I can't get her to walk right. So I have over 40 5 star reviews and I'm sure she is not going to be nice to me in review if I dont give her back some money...but I have a 7 day cancellation policy and Her dog ruined a 30 dollar shirt and she is definitely not being honest about her dogs regular behavior. Anyway even if I give her money back I bet my review will hurt me. I want to do the right thing but this is also my full time job now and they are well off and bringing her to kennel that costs over 100 per night while I charge a little over 60 for both. What should I do?