Simply Cancel it! Get your facts in order....and if you manage to get another gig....post some flyers near the offending club explaining WHY you're not playing there. Be soooo courteous that it hurts, and don't exaggerate one thing. He played hardball with you (cuz he could) Play a bit of hardball back.

This shit ALWAYS happens around St Paddy's.

Cheers

Rick

P.S. Find a copy of KENNY RODGERS' book on "How to make it in the Music biz" It's an excellent book.....even if yer not a fan.