Dog chewed up clothes.

Without proof it was one dog or the other (and you may still find out for sure who it was if someone starts pooping shredded fabric), I wouldn't accuse either owner; however, I'd mention it to both. Just because one dog hasn't done this in the past doesn't mean they didn't this time. My own dogs usually leave the laundry alone, but every so often one of them drags my underwear out into the living room while I'm in the shower. A dog who stayed with me before with no chewing issues tore apart a book while my boyfriend was in the bathroom on his latest visit. (In regard to that, I made a dog shaming pic for him, which I sent to his owner to show we found it funny, especially since the book he ate was "I Could Chew on This - And Other Poems by Dogs.") By mentioning it to both owners, you may get one to mention that their dog has done this or something similar in the past, and if they are reasonably sure it was their dog, they may offer some reimbursement. However, if you can't prove it, I wouldn't ask for any money. You may just have to chalk this one up to poor judgement leaving the clothes out and in the future be more careful what the dogs staying with you have access to.

Tough but certainly a valid question. You don't want to possibly alienate your guests parents. Chalk up to a learning curve. I had two guests last week. One of them ripped a hole in our couch cushion. But we don't know which one. It happened within 5 minutes while we were in another room. It's an old couch so we just flipped the cushion. hahahaha. I also hate confrontation.