Well name brand or not, the OP has my sympathy. I'd be really upset if that had happened to me.

Besides moving me to another room (that's a duh), I'd want the room comp'd, items that can be cleaned cleaned, items that were destroyed replaced or some $$ compensation (TBD) to offset replacing them, and some additional points tossed in to make up for the hassle.

Given the photos Marriott's insurance will presumably cover the $$ outlay; moving room & comp'ing is internal. The GM should take care of this promptly & then get his engineering staff up there to figure out what's wrong w/ the pipes. If it spreads to other rooms, s/he has a bigger issue on his/her hands.

Cheers.