Yeah, they did. There might be a third party involved but it was definitely the jocks who did it. More specifically, it was Caleb, because even the MC mentions at one point if you click on the alphas' writing on the wall that the handwriting is actually good. The irony with it being that he's a "reject", like Lily, who actually seem to have higher scholastic intelligence than the others who just focus on partying all the time. It's undeniable that the alphas took part in the trashing of the mansion. Whether there's someone else who persuaded them into doing it is obviously unknown, but it's concealed by DPC in the story by that the DIKs went and threw the dildos through their windows so that it just seems like retaliation from the jocks. It'll be difficult to find some kind of proof to support Vinny being mixed up in it, excluding Nick's room not being touched by them or the camera theories implying that the mansion's trashing was done in order for someone to install the hidden cameras without being suspected for it.