Chael is mad cuz it's gonna come out that his whole thing is an act. The reason Rogan told people that is cuz he respects the viewers. Chael is reacting like a pro wrestler that's mad that another pro wrestler told some fans "don't worry, we don't actually hate each other."
The whole "trade secrets" thing is dumb. Personalities aren't a trade secret. Also, it would be bad if Colby wasn't so goddamned awful at his own gimmick.