Thank you for trusting your question to JA today. I am a licensed attorney with over a decade of law practice and over 20 years of experience in the legal field. I’m happy to be of assistance.
You can file suit, but not for the things that you waived in the agreement. Instead, you have to file suit based on breach of that contract itself. You can essentially sue for the unpaid portion of the separation agreement. You could also ask the court to invalidate the entire agreement, based on this breach, but you'd then have to pay back everything you received.
I certainly understand the issue with being replaced by someone a different race than yourself (and the same as the others), but you also mentioned they are friends. Hiring a friend over others isn't illegal in employment law. It's cronyism, but that's just word with negative connotations. It's not a word describing an illegal act. So, to sue, you'll be running up against that fact. If the employer here can demonstrate that the plan was simply to hire a friend, then the person's race isn't really legally relevant.
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