So, about the Chad / Sage thing.
When you say your gonna out him, sorry bro, you might be all pro gay power and stuff, but just no. That last scene has them kissing in the OPEN in a gym locker room where any jock can come on them at any time all the while Troy is banned more or less from that gym being that he was kicked out. Heck, when the MC pass by, they don't even flinch. You act like being gay is bigger than everything else. From those i know, they just want to be treated like normal people, and to be honest, being gay in our society ain't that big of a deal anymore.
The point is, I don't think he wants to hide anymore and he's starting to accept the situation and started to take steps. Best thing to do imo is to go to him when his alone and tell him your gonna go with him and let him tell Sage what's happening and just wait outside the door for the afterward cryfest. (In a neutral area, the MC room at the DIK manor, off course, by the door/window xD ) No one said telling Sage is going to make everything known to the world.
Second, if the MC decided to say fuck it and out him, well, he would be perfectly justified. Chad sucker punched MC and provoked a fight. No matter the reason, the pictures or what Chad think is relevant, MC don't know that. All he knows is Chad attack him for no reason, and him saying fuck it my dude your gonna be my bitch would be perfectly fine by me. It's called you reap what you sow.