Raniere's relationships with Mack and other women suggest what we might term abusive relationships—if not physically, then at least psychologically—conducted under the guise of some sort of mentorship meets dom/sub situtation. Plus, some of the tactics he used to control these women almost definitely fall under the categories of fraud, extortion, or harassment.
Yet the idea that anyone here was actually involved in sex trafficking—i.e., forced or coerced prostitution—is incoherent under legal or common notions of the concept. This is a distinction that matters for reasons far beyond any concern for Raniere's reputation or fate.