No one forced him out, he wasn't suspended....he just decided to quit the IFBB all on his own..
http://blog.bodybuilding.com/OlympiaBlog/category/olympia/live-coverage/contests/photos/"The one thing I did find interesting were the questions that were inevitable and asked by the fans about the new PDI federation and the suspension of Lee Priest. For those of you who have not followed this drama, Lee was qualified for the Olympia but joined the PDI and did a PDI sanctioned competition. This was in violation of IFBB rules and he was suspended."
http://www.muscletime.com/news/latest/lee-priest-denied-reinstatement-to-ifbb/"The IFBB Professional League has denied the reinstatement of Pro Bodybuilder Lee Priest to IFBB competition. The IFBB reviewed events pertinent to his case on October 2, 2007 before denying reinstatement. Lee was suspended from IFBB competition for violation of Article 1.7 of the IFBB Professional League Rules prohibiting IFBB athletes from competing in non-sanctioned or non-approved "competition events" which:
"Includes, but is not limited to, competing, guest posing, giving a seminar, judging, officiating, endorsing or otherwise taking part in any capacity whatsoever in a non-approved or non-sanctioned competition or event. "
The initial suspension was the result of Lee's competition on September 16, 2006 in Wayne Demilia's PDI Night of the Champions.
Lee Priest was initially offered a 6-month suspension which he rejected due to pre-existing commitments he had made with PDI. Instead, he accepted a 12-month suspension.
Lee publicly announced his plans to compete in the 2008 Arnold Classic as it was widely assumed by Lee and most others that he would be re-admitted to IFBB competition after serving his 12-month suspension. "