I believe it may be a mix of individuals from both Diks and Jocks and Quinn may also have a hand in it I think she, Dawe and Tommy are all plotting away to get rid of their respective presidents maybe with the help of one or two insiders.
But Chad also received Arieth's cheating proofs, if I remember correctly. I can't believe Dawe is so smart to do such trick to avoid suspicion. And he doesn't seem the type who likes being a cuckold and share it to the world. Also, such plan needed a few fortunate conditions: piss Chad off enough to make him want to punch the MC (well, this one was easy, tbh) and hope Chad was going to punch the MC in presence of witnesses (witnesses willing to talk). If Chad attacked the MC with nobody around (and this almost happened), the plan would have failed. In addition, Dawe wedgied the MC and Jill saw it, right? The school could have punished both of them, even if a wedgie is way less serious... Well, anyways, I don't believe Dawe is smart enough to plot this, he doesn't seem much smarter than Anthony.
I don't know... Things seemed to be going pretty well for everyone, even for Tommy and Quinn. They didn't need to catch more attention on their business, as somebody already said.
For now, the only ones not affected by this mess are nerds and preps, right? Maybe one of them is plotting to get rid of both jocks and DIKs.
P.S. By the way, Jill and Tybalt were talking about a campaign, right? What campaign? I don't know how it works in American colleges, but I presume they also have students representatives and councils, right? Could it be a campaign for that role? Maybe assbreath Tybalt is plotting to eliminate the other possible candidates to impress Jill, without her knowing it.