Who's worse in this situation, the men having a private conversation, or the woman who was eavesdropping and decided to make this into her personal witch-hunt? Posting their pictures online was far worse than what they said. The fact that she sees herself as "Joan of Arc" just shows how self-righteous she is. I would be very concerned if I were working with her.
I'm not on the side of Adria in this fight, but I don't agree with your points. First of all, they were not having a private conversation. Presumably Adria wasn't utilizing some telescopic microphone to record their whispers. She was just sitting near them, and heard them speaking. That is not eavesdropping.