Would the average attacker, though?
It's a question about not touching an easy $15k, in exchange for a chance at a bigger score.
I'd assume most attackers wouldn't be able to resist securing the low hanging fruit first.
And even if there's a parallel move, it's even less likely they would leverage everything but the $15k, so OP would still receive a realtime indicator of compromise.
From a game theory perspective, it's a pretty compelling trap for OP to get what they want.