1. They say "no im not exploited" because they are afraid

2. They say "no im not exploited" because they are not exploited

You gain no information from interviewing them. No vice unit has the resources to do a top secret clearance level check on them to confirm externally they are not exploited. To act like the two can simply be distinguished really is willfully ignoring the very real problem that you cannot verify the honesty of the person through any line of questioning. I suspect despite the foaming mouthed progressives claiming it's some puritanical hatred for women the reason for it still being illegal is because of this exact problem. There's no actual way to confirm this concept of "consent" in a legally rigid frame of reference because nearly every aspect of a sex workers job can be coerced.

EDIT: Somewhat hilarious I'm getting downvoted for an opinion. Groupthink HN truly the pinnacle of individualistic moral superiority.