wow - I hope the turtle was ok? I would suggest speaking to a specialist pet shop/breeder of these turtles as they might have some suggestions in the event of this happening. You might also get some advice from an aquarium that might have experience in clearing up after turtles in general...
You haven't mentioned (not that I can see) if you can drill into the bedtroom walls at all? Reason for mentioning is that you can fix shoe holders and some TV stands to walls - if the room is rented you might want to check if you can start drilling into walls first though
