nope, you never report them because the story usually goes... player gets threaten, botter reports for harassment, botter gets banned. (I've seen many of these before) never report for harassment because blizzard investigates both parties (another reason for people who report botters and are botters themselves to not report since you risk your own account).
If you report other botter for any reason, even if he reported you, you became like him - rat You are just a stinky snitch who don't deserve to breath I can forgive lot of things, but snitching never.
People that send this crap send it to 50 people hoping that someone will send them 10K gold. He will not care to follow up with that threat. Its a type of ponzi scheme.
