I don't think there is anyone to call or notify. You should consult with a lawyer to see if you have grounds for a defemation law suit. It is hard to say without knowing what the Board members are saying because I can think of several defenses that might apply such as opinion and common interest priviledge.
I am a former federal and State prosecutor and now handle criminal defense and personal injury/civil rights cases. Feel free to check out my web site and contact me at (212) 385-8015 or via email at Eric@RothsteinLawNY.com. The above answer is for informational purposes only and not meant as legal advice.
Hire a lawyer. The best and first thing the lawyer can do is send a letter informing these people of the fact that you are represented, documenting the fact that these individuals have said defamatory and false statements, and alerting them that if these actions do not cease and desist, you will consider further action - including your remedies at law. That should put 90% of individuals in line. For the tough nuts, you may have to bring suit.
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