Best thing is to stop any and all attention. Perhaps one last message. That he missed his appointment, which was not your fault. He wasn't courteous to call and explain, so being this is your profession you filled the time he missed.Then tell him you do not want any contact with him at all. Explain any further contact will be unwelcome and you will take measures to protect your self, but only if he makes it necessary.
Then block his number and filter his emails. (Save them, if he does stalk you they can support your obtaining a Restraining Order).
I've heard some creative options, asking if his wife/gf would like to talk about his rude threats. Seems risky, but some of the PB ladies have backup if you know what I mean.
I heard one had the guy come meet her at a big hotel, asked what kind of car he drove so she could get him free parking with the gaurd. There was no gaurd, adn her friends tagged his car as a woman beater!
Sometimes I think the whole hustle has gone downhill. I haven't had too many problems thankfully.
Again best to ignore the jerk, other than to report him on that "problem client" website. In box me for details...
QB