Yes, it is appropriate for them to have a mediation session in that it is a reasonable (not mandatory, but reasonable) step in determining what happened and in finding a good resolution to any issues or problems. The company has to investigate your complaints and take good faith and reasonable steps to ascertain the truth then, if they conclude you were discriminated against or harassed on a racial and/or gender basis, to prevent any recurrence and mitigate any harm done; but that investigation can include having the two of you sit down and speak with a 3rd party or mediator present. So you have to attend--if you don't cooperate, the company could drop the investigation in good faith based on your noncooperation and failure to give them a chance to address the issue. But you don't have to agree to anything you don't agree with; and you do not have to put up with harassment at that meeting, if such occurs. Attend the meeting; answer honestly and discuss the matter professionally; take notes about what is said or discussed. If the meeting turns into a lynch mob (so to speak), don't react with anger or insubordianation--again, just take notes and don't concur in anything you disagree with. In and when it becomes clear that the company is not taking your complaint seriously, is endorsing harassment or discrimination, etc., then contact the federal EEOC or the state's equal/civil rights agency to file a complaint. But you have to give the company a chance to handle it first--they only become liable if they fail to do so--and maybe, with luck, they will resolve it properly.