I'm afraid all the signs point toward someone who is homegrown.
As far as tonight's performance, I'm still a little confused here. I read all the explanations about the phone booth, the cell phone etc... And they make sense.
But I'm just wondering: If the perp left Moose a phone number, WHY WOULD MOOSE HAVE TO ANNOUNCE IT ON TV? Why would he have to tell the perp: We're ready to take your call? Why not just have someone ready to take that phone call?