> trafficking charges are a distinct group from prostitution

Incorrect. Sex trafficking includes (among other commercial coerced sex) any instance of prostitution which involves anything other than free and full consent from someone with capacity to consent to sex; minors by definition lack capacity to consent, so pimping a minor is an offense which falls completely within the bounds of sex trafficking. (Unlike simple pimping, solicitation, etc., which may overlap with sex trafficking, but also include acts which are not sex trafficking.)