Maybe there is a medical reason why she is wetting the bed too. She could have an UTI. When she does have to go, is there a sense of urgency? Like she will pee her pants if she doesn't go right away? Does she go more often than she normally does?
My daughter has been potty trained since she was two, and will be four next month. She has recently started to wet the bed every so often (something she never does or did, even when I was potty training her). She has been battling a UTI for a month now (taking her to the dr's again on Thurs) but she never complains about pain, so other than me knowing the signs of one, would never have had her looked at.
I would talk to the parents and find out if anything has changed at home. Could be something small and insignificant to them, but to her unsettling. I don't agree with the way they are handling things. I agree with Crayola about buying some cheap pullups and giving them to her at your house.