The difference with this one and other theories/hypotheses I have is that, while those others are about coming up with plausible assumptions based on 1 or 2 little hints, the Dawe/Quinn conversation has 4 fairly conclusive pieces of evidence that what they talked about was most definitely the deal for the pills. Saying that it wasn't or that they also discussed a plan to leak the Cathy pic on the DIKs account is what is, in this instance, a theory that's totally out of left field and not backed up by anything.
I still view Quinn as a prime suspect for the Cathy pic though, but I don't believe she will have conspired with the Jocks to do it if it was her doing. More likely I see it as Quinn unilaterally deciding to do it thinking that by getting the DIKs in trouble it would take some of the heat of the Jocks and she could try to persuade Dawe to make good on their previous deal.