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Yes, because there is no agreement yes. Unless and until you sign that document, there is no confidentiality attached to this situation at all by law. Furthermore, you stated that the agreement only imparts confidentiality on you not them (only the disparagement clause was mutual). If that's truly the case, they'll never have a confidentiality requirement even after they've signed it. If that is not what you meant, then they still have no confidentiality requirement until BOTH parties have signed the agreement.
No, you would have no legal grounds here. He can legally tell people that you have been let go because, presumably, they are prepared to terminate you whether you sign the agreement or not. No employer gets to this point if they are going to back down simply because you refuse to sign the agreement. If you don't sign it, they'll just terminate and then not have the benefit of your waiver of suit. They have to go into this prepared for that possibility.
Regrettably no, there is no cause of action for you here.
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