I would not rely on the Internet to ascertain whether a recording is permissible. It should not cost much to consult a local lawyer. If you show up, you are acknowledging their rules. No court can touch a JC b/c of the First Amendment. Your remedies are very limited. In fact, I don't know if there are any remedies. This is a private, religious group not a court of law. No advocacy exists within the Witnesses for targets. It is a penalty imposed by a totalitarian religion.
What does a recording prove in practical terms? I believe the rush to record is a response to even the playing field when you have absolutely no control.
This is a group that destroys records on legal advice (where the normal member is NOT represented) and insists on public pay phone calls to report pedophilia, even though they have zero liability in their view. So much evidence against their total lack of due process concerns and fundamental fairness exists in the public record.
Please I understand the discussion of reasonable expectation of privacy (which would take weeks to research). I indulge in queries, too. The drive to record could land you with serious repercussions far worse than the predictable course of a JW.
Unless family shunning is blackmailing you, the best way is not to bow to their authority. Don't engage with the elders. They have no power over you. Recording the conversation is still playing by their set of rules. These rules have no power outside of the Witnesses. It is very much like vodoo or Santierra. The belief is what harms you, not any actual magic. Beware the impulse. So much is at stake that a simple legal meeting makes sense.
If the local lawyer deals with them in a manner of let's make a deal but protect my client's interests, a good solution may result. Recording it shows that you don't belong in the Witnesses.
All the protections flow in only one direction. A JC may not be all members in the KH business. The far better course is NOT to accpet their legitimacy. If you do, they own you, recording or no recording.
Society, in general, recognizes more and more privacy rights.