Interesting issue. There is a mediation and settlement discussion privilege in CA, and parties can agree to keep settlement agreements confidential.
However, facts that are otherwise known are not shielded from discovery simply because they're mentioned in mediation or in settlement talks.
Moreover, nothing in either privilege would across the board prohibit the creditor from speaking with you. They just don't want to be deposed -- looks like you may have to subpoena them for deposition.
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General rule is that what is said in mediation stays in mediation. Depositions can be held in ongoing cases in certain cases even with non parties, if properly served, but, unless the company you are talking about is in BK you just continue on to get (hopefully) a judgment. If they are insolvent, they cannot afford an atty so, you are in the same boat apparently. Get the judgment and try to collect is my 2 cents.
I concur with the advice you have received from Attorneys O'Brien and Kaufman.
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