Sorry poor terminology,
'Misprision of felony' ... The federal definition of misprision requires that, "(1) the principal committed and completed the felony alleged; (2) the defendant had knowledge of the fact; (3) the defendant failed to notify the authorities; and (4) the defendant took affirmative steps to conceal the crime of the principal."
It'll still be your ass if she gets busted and any proof you know about it surfaces... like this message board for instance.
My sister did 3 years in federal prison for a similar scenario, any indictment would still be board reportable. If it were me, I would consider my need to maintain a license and career over her need to play bad girl. If you can get her into treatment to help her and save her license do it. But "minding your own business" puts you both (and her patients) at risk.