I think it might be possible. Considering the number of endings on AL and that there was an ending with the MC's ex, which was a side character, it can happen on BADIK.
I have a save in which the MC is a huge dik and I believe if you don't focus on Sage (I'm sure the drama on the HOT's will be the main focus of her route and perhaps there'll be an option to stay on Quinn's side), it may be plausible to have an ending in which the MC actively takes a role on Quinn's shady business.
Btw, I'm curious about what's making Quinn and Riona really worried about the money. They offered the threesome because they were desperate for it. What really caught my attention is that they got high for the threesome, but Quinn didn't get high for the CUM-petition and Riona didn't get high for the gloryhole. Their financial situation must be really bothering them.