He said that to talk about it was “disgusting”.
If that’s what he said, then that’s true enough.
That being said, my guess is that it’s all part of the set-piece, designed to showcase Clinton as being so important, so much better than Sanders & O’Malley, that she is entitled to make them, and everyone else, wait even when she’s doing the same trivial things that us lesser mortals do, like taking a wizz.