If it were just paid shit posting as you describe then I don't think it would be that big of an issue.  It appears (at a quick glance so maybe I'm wrong) that your friend was promoting an outright scam knowingly.  That's the sort of thing that just doesn't go away with a thread and a good story.  I'd say if you handed away your account years ago, that's an equally bad offense and likely won't get you much sympathy around here.  You're probably risking more negative feedback to be totally honest.  All you can really do is roll with the punches and try to rebuild a reputation.