Oh, we definitely can... but I suspect this will need even more out of the players. Quinn is veement on digging her grave as deep as possible.
For the players to save her, we need to not be on MaJo's path, buy girls from her and spend a lot of money on her, be a DIK on the late game (meaning you also lose Jill's path), you need to succed on the mantion repair minigame because you need Rusty's car. I bet there will appear new switches, like MC not being bothered with the drug stuff, him trying to beat Vinny, not being on Lily's path, maybe being understanding of the shit she did with Rio, not being on Zoey's path and maybe more.
We need to do a whole lot and sacrifice a lot to be able pull Quinn out of the hole and the darkness she willingly entered.