She was 17, and at that point in time 17 was above the age of consent in the US. It was changed to 18 around 2002. So it would have been completely legal back then.
This is incorrect. The age of consent in the USA varies based on state, many being 16, some being 17 and 18. However, the age of consent for sex trafficking or prostitution is fixed at 18 by federal law.