Being enrolled in pre-law seems at complete odds with the lifestyle she was living and her sentiments on Twitter. Why not music business? Journalism? Marketing? Something to make the festival life permanent? It seems school was something her parents wanted, really, and could be a factor in wanting to disappear.
If she had a prior federal drug charge, it wont show up in normal court record searches. Pacer is down for maintenance or I would check it - someone remind me this weekend.
For the sake of argument, and in relation to your first comment regarding school - if she had a prior drug charge, admission to law school, let alone being admitted to the bar, would be virtually impossible.