How do I get a copy of my Foreign Expat Cancellation Letter?

I am in Beijing and my employer won't give me a copy of it. He has threatened to make up lies to keep me from working in China or Beijing ever again. I don't know what to do or how to stop him. The school he works at has people working on a student visa...the school doesn't report the proper income to pay the correct taxes. Also no one at the school has the proper degree ot certifications. The principal has a Bachelor degree in Business. If I tell the Chinese Foreign Expat Bureau will they do something to help me...? PLEASE HELP ME...I AM SCARED TO DEATH...