In the meantime to protect your mattresses ...

Place a shower curtain directly on the mattress. Place an extra thick towel or two on top of the shower curtain. Then put the fitted sheet on over all that. It's easier (and cheaper) to wash linens than it is to try to clean and/or replace a mattress.

Hoping y'all get the situation figured out sooner than later, and try not to go too hard on the poor little fella ... It may be something he can't help and it would totally suck to be getting into trouble for something he couldn't help!