I agree. I don't think its them. I think he may have seen that page, or maybe he knows of their sierra times web site.
And yeah, could be setting them up, but I'm inclined to think that he may have been like them in having the same concerns, and for whatever reason, has lost it big time! jmo
His leaving the card with the message was meant for them, not LE. He wanted those that knew that letter, knew that page, to know that he/she was one of them. That's what I think.