You haven't really given us enough information to give specific advice. What is the status of this evaluation? Does it count as a fail on your record? Will it need to be disclosed to anyone in the future (eg for licensing or credentialling), or is it a piece of paper that goes in a file and will never surface again?
What are the procedures available at your program to challenge an evaluation? Would they be completed before you leave, or are they still available to you once you have left? Would starting a complaint procedure affect any future statements you may need the program to make on your behalf, such as licensing and credentialling?
How secure is your position in your new program, and would it be affected by this evaluation? Would it be affected if you decided to fight this evaluation and ended up creating a public stink because it raises a question of racism (which can easily turn into a big and unpleasant fight - not many people go quietly when accused of racism, and a very common tactic is to try to discredit the accuser)?
Does the evaluation include facts which you can prove are untrue? Does it include opinion that you can demonstrate is contrary to the facts or is not supported by the facts? Does it, taken with the previous evaluation and the surrounding facts, demonstrate racism?
If you don't want to leave the allegations in the evaluation unchallenged, but at the same time don't want to start formal procedings, is there scope for you to add a document to the file stating that you do not accept specified statements in the evaluation but as you are leaving the program will not be taking the matter further?
Is there anyone who does know the specifics of the situation who can advise you? Resident adviser? Chief resident? Lawyer?
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