Your case is extremely difficult to analyze based on a single paragraph. It would be unwise for anyone to give you a "yes" or "no" answer to your question.
My frank opinion is that your case does not sound terribly strong.
On the other hand, you may have more leverage than you think.
Finally, you need to protect your right to get unemployment compensation which could be jeopardized by such an agreement.
Spend a few hundred dollars on getting a lawyer to review your situation and the language of the agreement. It'll be worthwhile.
Have a local employment attorney review the agreement and your facts before you sign anything. It really isn't possible for an attorney to give you any advice about an agreement without reviewing the entire document. Good luck.
I agree with the other counsel on this question. When there is a written agreement involved, it is a good idea to have it reviewed by an attorney. It shouldn't take much of his or her time to give you a consultation on your potential claims.
This response is meant for general information only and does not constitute legal advice. This response does not create an attorney-client relationship.