who sent the HOTs to the Preps party?
Quinn doesn't have that power. then it is evident that Quinn advised Sage that way for her own interests, but Sage took that advice thinking it was the best solution for the HOTs as the Preps paid more.
the idea is Quinn's, but the decision remains with Sage.
if Riona had said it was Quinn's idea, what would essentially change? Sage wouldn't have made a good impression on it anyway, it meant either Sage takes Quinn's advice passively, and at that point it's better that Quinn be in charge directly, or that Sage agreed with Quinn's idea.
shady deals are a separate chapter, prep party was boring regardless of Quinn's trades, and that's what HOTs complain about