It's obviously far from trafficking or slavery if the adult lady volunteered for and is happy with her situation and choices.
Why not let the grown ups make their own choices that don't affect you?
If you're trying to save everyone, you're going to have to open your eyes a whole lot wider: How many arranged marriages can you report and fix and save some girl from? Or marriages of convenience, or family pressure, or pregnancy, or financial need? Or unwanted children? Or runaways from abuse? Or overworked against the law? Or underpaid against the law? Or discriminated against for any of 100 reasons? Or innocent children brainwashed with their parents' religion? Or band members, waitresses and hostesses who must endure a smoke-filled environment? Or pilots who breathe recycled, contaminated air in flight while being zapped with unknown levels of dangerous radiation? Etc.