It depends on state law. NC only requires one person be aware of taping of conversation, that was at least 5 yrs ago, and laws can change. So check laws in state to do taping.
I think DC also has 1 party consent. But this was an open room conversation. Expectation of privacy may not apply.
Could be a rope-a-dope. And doesn’t really reveal anything except personality conflicts.
I have that understanding in NC also but Linda Tripp supposedly broke a law in MD by taping the cigar girl without her permission. It depends on the state.