You are right about everything.
But everything you wrote can be avoided by the MC.
Tybalt has no real friends and if the MC makes peace with the Preps at the dorm party, that bomb is defused.
Josy and Maya can testify that he did not start a fire during the Preps party, that he did not activate the sprinkler system. This proves that Tybalt is lying. However, that will not stop Tybalt from continuing to lie.
If the MC does not respond to Jade's advances, there is no need to worry. Jade will respect, perhaps even appreciate, the MC being true to his LI and to himself. By doing so, Jade also acknowledges that the MC has learned something in her lessons. I believe that Jade will be this way for Maya, Josy and the MC.