Val i think is as close to sure thing as possible, she was nowhere to be seen in the school previews, surely there will be something with her after the cliffhanger.
No idea what can happen on the Elena path, maybe they at least kiss while leaving school?
Most of the previews images i believe where on Layla with Elena still in love route(aka possible throuple).
Other than that... things that i think can happen.
Ethan attacking John(and Iris) in the garage is possible.
MC getting blindsided by Ethan after agreeing to have a sitdown with Zach.
Lakeyin... i'd probably wait for the parties that are coming to reveal that, it will make it funnier... let it stew for the moment
If Erynn shows up i think it's more likely it will be something bad related to Ethan than hanging out and having fun.
Alexis... not even that.