@H2O MAN,
I don't have to prove a negative.
However, the FBI agents that first interviewed them said they had the information claimed to come from waterboarding prior to that waterboarding.
Since there is no evidence of any other information and all information claimed to have come from that are in dispute by sources that would know, it seems you are the one that doesn't have any facts to back up your position.
Since you claimed the waterboarding worked, please tell us what information they got from waterboarding that the didn't already have.