Nerds are out of luck in their war against DIKs. (It's called Frats War, but it's really only aimed at DIKs).
The photo of Katy, it's only because Rusty is close to her that he was able to convince her it was a hack and therefore not because of them. Without it, we'd have had Rusty kicked out of the DIK presidency at best, and a dissolution at worst.
Then they moved on to what should have been the equivalent of the nuclear bomb with the video sent to Burke. Again, it missed the mark completely.
Stirring up tension with the Jocks is pointless, it gives an unpredictable result, and can't really harm the DIKs (in theory, except that it was actually the most violent blow, since it led to the house being ransacked).
All this was done at almost the same time, or at least very quickly, and since then nothing. Now they've decided to send anonymous letters to the Jocks and Tybalt. Knowing that Chad and the MC have been talking, the letter to Chad isn't going to work.
What will this trigger? I imagine a sort of first step in judging the MC's choices, but I can't imagine the nerds knowing anything incriminating about the MC. Derek may be in trouble for stealing the moose head. Other than that, it's just stupid jokes, and nothing really problematic apart from Jade's video.
So what's it going to be? A fight with the Jocks, and a totally discredited Tybalt complaining that someone pissed on his bed? I can only see the video doing damage, but it's not a canon event, so it can't be just that.
Either the nerds have unsuspected weapons, or they're not very good at waging war...