plus it makes sense that Oliver would immediately go to Rose to know WTF she suddenly got so much money (and ask for more obviously)
Agreed. I honestly had this fear of the potential consequence during Week 2 that the immediate approach MC was taking with a huge payment to Oliver, but not the full amount, was going to cause more trouble than the status quo, thinking the response we got is what would happen. Yet sense the game pressed the "payment plan," rather than offer a player consequential choice (e.g. cheating or staying faithful to Hana), I figured "it will be alright". I am starting to feel a little repetition in the effect that our current decision will also make things even worse, as August attacking, but not killing, Oliver will definitely escalate things, and the police arresting him will only hold him for a short time (i.e. less than the two weeks to the end of the competition), while seizing/shutting down his criminal operations will make him even MORE desperate for cash, i.e. a defenseless single mother he can shakedown.
However, his threats to Rose if she can't pay, and accusations of MC's ulterior motives, makes me believe that Oliver's true goal isn't the money, it's Rosalind's body, either for himself or to pimp out, thus even paying off the full debt won't make him go away.