To continue with your reasoning, why would they have Jennifer do a striptease when you brought Sophia in for that?If Aiden knows Sophia is following him or if he catches her watching, possibly even with her hand in her panties, the whole blackmail route is over. Aiden has won - king takes queen -. Aiden then realises that the resistance is just an act, Sophia's moral outrage is just for show and he can reap now. This is no longer a blackmail story but only seduction.
I see only one option: Sophia follows them and will watch the whole scene. As you say, it's unlikely that Aiden will catch Sophia, I'd bet on someone else making Sophia run or catching her.