Can former employer violate oral agreement to list as rehire status

I worked for a state agency and had conflict at a new position. I was given a choice of being fired or resigning. The HR director offered me some severance pay, to help me get UI benefits, and to "... have no black mark on my record, and be eligible to compete for other jobs with the agency."

I received the severance pay and the UI benefits. However, after over a year looking for a new job, I did an open records request with the agency. They had actually listed me as no-rehire, despite assuring me twice that there would be no black mark against me, and that I would be eligible to compete for any open positions.

I have the conversation recorded where the HR director made the offer. It details me asking what the agency was going to do for me in exchange for me resigning, and him voluntarily offering those three incentives. I then agree and say I will come by and sign a resignation letter, which I did.

Since then, I have been unable to secure a new job. I have had a couple near hires in the job hunt. Prospective employers have selected me as the best candidate from interviews, then suddenly stop talking to me when they start to call my references.

Do I have any legal recourse for the HR director lying to me about what kind of reference I would get for potential future employers?