Seeing as you're not listed in the topic, did you pay him?  Is one of these accounts listed one of your alts?  Did he just not get around to linking you with another alt yet?  I'm very curious about this.

Also, if you're being blackmailed, post the proof here and/or report that to a mod.  I don't think that's compatible with forum rules, but I'm not 100% sure about that.  It's definitely not ethical--IF he did send you that PM.