Well.. the only way to really figure it out.. which it doesn't sound like they can do unless they didn't toss the "shit" out... is DNA testing to prove wether it is false or not.
It may not say wether the honyemooners setup the prank... but if one of them shit on the bed... the tests would show that they had.
I find it funny, but I just can't see that happening to be honest. But you never know... just take a blacklight with you the next time your at a motel/hotel and run it over the bed with the lights off... you may just be suprised yourself.
