Does Confidentiality End with the Agreement?

Recently, I was able to help settle a particularly thorny contract dispute. Because tempers had flared and there appeared to be some bad blood between the parties, I was concerned about leaving the parties in the room while I brought the terms to the mediation coordinator so that she could type up the settlement agreement. When I jokingly asked if I could leave everyone in the room without the deal falling apart, counsel for one party remarked, “Don’t worry, we have an enforceable oral agreement.”

As I left the room, that seemingly innocuous comment got me thinking. Could the parties call me to testify that agreement had been reached and ethically, would I be able to testify? My initial thought was that upon agreement, the mediation ends. The terms of the agreement are not part of the mediation session. I recalled a similar discussion in my training class, but when I got home, I could not find anything further in my notes.
Further research revealed that the rules set forth by the Georgia Office of Dispute Resolution for court-annexed programs state:

Neither the neutral nor any observer present with permission of the parties in a court-annexed or court-referred ADR process may be subpoenaed or otherwise required to testify concerning a mediation or case evaluation or early neutral evaluation conference or, unless otherwise provided by court ADR rules, a non-binding arbitration, in any subsequent administrative or judicial proceeding. A neutral’s notes or records are not subject to discovery. Notes and records of a court ADR program are not subject to discovery to the extent that such notes or records pertain to cases and parties ordered or referred by a court to the program.

and further that:

Written and executed agreements or memoranda of agreement reached as a result of a court-connected ADR process are enforceable to the same extent as any other agreements. Oral agreements shall not be enforceable.

So, in the context of a court-ordered or court-annexed program, the answer would be a clear and simple, “No.” No, I could not be asked to testify and contrary to the attorney’s belief, no, his oral agreement is not enforceable.

But what about private mediations? The Rules of the Georgia ODR would likely be instructive, but not conclusive. Is the existence of an agreement protected by confidentiality? Can an oral settlement agreement be enforced (putting aside the Statute of Frauds for a second)?

Of course, it would be foolish to allow parties to leave the room without something in writing. But it is common to allow the parties to memorialize the terms in writing themselves, so that attorneys could add all the wonderful boilerplate they feel is necessary. In those cases, I would, of course, create a memorandum setting forth key terms of the agreement which all parties would sign. Even then, however, it might be necessary to clarify some points. Could I forced to testify that the amount was $30,000 not $35,000? Or that payment was due by certified check by close of business Friday, not close of business Monday?