Here is how it is actually written:
Notice how the MC has already figured out that Quinn wants to pimp out Maya, but inexplicably stops short of telling Maya about Quinn's prostitution business. He tells her that Quinn uses the girls to make money, and that she is evil and not to be trusted. Maya fails to put two and two together, then goes to Quinn's defence and says that Quinn isn't evil. Which is very odd since she had just been crying over how Quinn humiliated her, and had also just watched Quinn taser the MC in the throat until he passed out. This is one of the many reasons why Quinn is the worst written character in the game. Everyone who could and should be warned about her worst kept secret just doesn't speak of it for no reason at all.
Of course she knows everything. Anyone who reads the full conversation can see that.
As usual, Quinn fucked up by misjudging a situation. She talked Mona into meeting a client, but didn't tell her that client was Stephen Burke. Mona was a "go-getter" because Quinn was letting her believe that she would just be banging college dudes, and Mona panicked because she was unprepared for situation Quinn put her in. Quinn figured that Mona wouldn't have the guts to refuse Stephen, and would give in under pressure. And she was wrong. As always.
Not strange at all.
Quinn is making a very standard veiled threat here against Mona by playing the classic "Nobody will believe you" card. That's why she asks her "Do you think Professor Stephen Burke will allow a student to solicit sex on campus?" It's a rhetorical question used to get Mona to think about what will happen to her if she doesn't shut her pie hole. Who will people believe? An upstanding and respected professor, or some random girl who is whoring herself out. That's what Quinn is doing here.
Not paradoxical. He gave the grant in advance, then revoked it when she failed to fulfill her end of the deal. Then he expelled her.
Because she already spilled the beans to Lily. She's a lose end and Burke needed her gone.
This ain't rocket appliances, buddy. The whole situation is pretty clear cut. The only mystery about Quinn's restaurant is why the hell the MC doesn't tell anyone about it?
He starts to tell Maya, but then stops short and refuses to elaborate after she asked him to clarify his perplexingly vague warnings about Quinn. He doesn't ask Sage about it either, even though he's had three perfect opportunities to bring it up with her. Maya, Josy, Sage, and Jade should all be furious with the MC when Chekhov's gun finally goes off. Bella and Jill aren't likely to be too impressed with the MC either.
It's so stupid that DPC keeps propping up his writer's pet like this. The MC was angry with Maya and Josy for their lies of omissions, so he's being a massively hypocritical douche for doing the same thing now. If the MC had told Maya and Sage, and they wouldn't believe him without proof, then it would create a scenario where Quinn would be forced to cover her tracks while the MC tries to expose her. Quinn could've been built up to look like a clever mastermind by keeping things going under scrutiny, instead of just looking like a bumbling imbecile that constantly screws up everything but magically avoids all fallout because the MC won't say a damn thing to anyone ever.
The... I... what the fuck are you on about? Sage doesn't have a girlfriend, and we already saw Sage cow Quinn into submission earlier, so we know that she doesn't need any protection either. And even if she did, there would be no need for a convoluted scheme like that.
It would be trivial for Burke to get rid of Quinn. Just have security do a surprise inspection of her dorm, and then kick her out for all the various drugs she has lying around. Quinn can't do jack shit without Stephen. Everything she said to Mona also applies to her. Nobody would believe her any more than they would Mona. Probably even less considering her appearance, behaviour, background, etc.
Only thing it will result is you all become like Jim here ^ 
