Daniel, played by Donald Sutherland, is the Dean of Admissions and not a student at Faber College. He is not involved in the food fight and wouldn't be the one to tell Principal Wormer who started it.
It is Bluto who starts the food fight, and it is implied that he is doing so intentionally to get the fraternity kicked off campus. It is not a major plot point in the film who started the fight, but rather the chaotic consequences of the action.