There is no way anyone could flush a book the size of the Koran down any toilet. A book that is about 6" X 8" X 2" will not fit through a four inch hole.
None of them thought about how ridiculous the statement was on its face, because they have no idea of the size differential, and they don't have the foggiest idea how a toilet works!!
I heard a rumor that it was a detainee that ripped the Koran page by page and was flushing the pages, hoping to stop up the toilets. He was protesting. Why didn't they print this version of the rumor. Oh yeah that's right, because it was a rumor. Not substantiated.!! Does that make sense?
Have you heard any of the talking heads make this point? Guess they don't think we peons have enough sense to know this. The whole concept is laughable.
If the pages were used individually as toilet paper it would.
Use a little imagination. It could have been a small version (I understand that 1x2 miniatures have been printed for use as talismans) or the book could have been flushed down page by page (as is alleged some of the detainees did to try to stop up the plumbing).