It is impossible that the Alphas are not responsible for the ransacking of the house. If you look again you will see the dildos. (in the dining room on shelves, in the future MC's bedroom on the floor, ...)
These are the same that the DIKs swing through the windows of the Alphas (and of course the same that the Alphas had thrown on the DIKs). They have quite particular shapes or sizes.
Someone should have followed the DIKs, seen them throw the dildos at the Alphas house, recognize them on the fly, then run off to the nearest sex shop to buy the same ones, and then come back to campus to ransack the house. It's not possible.
The Alphas took the instruction from Chad very seriously - don't mess with the DIKs for fear of having their frat shut down. So why would they trash the DIK's house in the first place, when they were already restraining themselves, and then spray paint their logo everywhere, totally incriminating themselves.
Sure they might want revenge because the DIKs threw dildos into the Jock's house, but that was obviously in retaliation of the Jocks starting that bullshit. So for them to feel compelled to do it again is pretty fucking ridiculous (but to be honest, that's the exact kind of stupidity that fuels never ending feuds).
Also, why did they absolutely trash every single room, completely, except Nick's room. And why was Nick so cagey about the fact that his room wasn't trashed, and why has he been acting guilty ever since?
I'm certain it's a frame job. Someone wanted to get something from the DIKs mansion, or trash it for revenge or something like that, and that person has an inside man - Nick. And who is Nick pals with? Vinny, the ex-DIK with an ax to grind.
It would have been smarter if they trashed Nick's room as well, even if just superficially, as leaving it virtually untouched does raise suspicions (that's why Nick tells the mc not to tell the others). Here's the exchange between Nick and the mc:
mc: "Dude, your room..."
Nick: "What about it?"
mc: "It's so clean!"
Nick: "Yeah, I was lucky. They barely touched it."
Nick: "I managed to clean it in a few hours."
mc: "Congratulations."
Nick: "Thanks! Don't tell the others, though."
mc: "That it's clean?"
Nick: "Yeah, I don't wanna rub it in. Especially to Jacob..."
mc: "Yeah, it's horrible what they did to his drawings."
Nick: "Yeah. I gave him a gift card to the art store he loves."
Nick: "I hope it gets him going again."
mc: "That's nice of you."
It's pretty obvious that Nick feels responsible for what happened to Jacob, that's why he's buying him vouchers. I doubt Nick knew exactly what was going to happen, but we all know Vinny is a fucking psycho (look how he trashed his own room when he moved into the Library in that episode 5 prologue).
I think there's more to the ousting of Vinny from the DIKs that just he and Tommy didn't get on. We know from Quinn's scene with Buddy that Vinny is a drug dealer, and more successful that Quinn. There's something in all of that that involves the DIKs mansion, I'm sure of it.
Regarding the dildo, Nick could have just mentioned that to Vinny, and Vinny used it as part of his frame job, either stole the dildos from the Alphas or something like that.
I think the alphas are morons, but I don't think they trashed the mansion, I think Vinny was responsible and Nick knows about it.
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