Interesting theory, but it all comes down to motives. It's unclear why Quinn would go to such lengths to frame a fraternity that was a very important client to her. I've already mentioned that Vinnie's appearance at the party in episode 9 could indirectly indicate that he was involved in the leak of Сathy's photos. He could easily have gotten to the party in episode 4 through the library (as we learned in the game, the library is an informal back door). It's no coincidence that that's where we eventually spot Nick (because he's the one who led Vinnie into the mansion). Riona noticed him, but didn't say anything. He could have gone from the library to the dining room and from there to Rusty's room. Why did Vinnie show up in episode 4? He probably found out about some kind of deal between Tommy and Quinn through the hidden cameras.
Secondly, Quinn's theory is hampered by the leak of Jade's sex tape. How could Quinn have gotten it? The most obvious possibility is that the video was obtained during the attack on the Deeks mansion in episode 5, when the intruders took advantage of the Deeks' absence. Quinn was busy at the time and it could only have been done by someone who knew the password to the safe. And Vinnie did.
And finally, one last thing. DPС has done a great job of putting Quinn, if not on the path to redemption, then making her seem like a victim. Uncovering the real truth will nullify those attempts, making all her actions seem hypocritical. The ending of episode 9 implies that Quinn and Tommy are teaming up against Winnie, but all of that will go to waste if Quinn is really behind all of this.
This would be interesting in terms of plot and drama and the player would have to decide whether to trust Quinn in the future, whether to help, support and so on, whether to hide the truth or expose Quinn. Too many variables, I guess Vinnie would be the perfect villain to suit everyone.
Quinn's an adventurer, but she's not likely to set Rusty and Tommy up like that, considering how much she values his friendship.