I don't like lent in and on my pocket carry guns but to find out whether or not that lent is a problem, just let her carry it so the lent can build up, don't clean it or anything and take it, as is, and shoot it. If it works, then lent's not that big of a deal (which I don't think it is really), if not, it should be eye opening for her. Pocket holsters aren't all bad, I use a Remora for both my CM40 and CW380.
I've done this a few times with a minimal amount of lent and never had a problem, but with that much, it wouldn't hurt to try it out and if it still functions fine, it'll ease your mind too.