There's also things like "I was recording this for notes that I could review later." You can also determine if they have a reasonable expectation of privacy. They do not. This is how Wal-Mart records you without permission while you shop.

I've read a book or two on private investigator training because I want to take the test in my state at some point. One book I read talked about recording someone through their window and it was admissible in court. They didn't bother to draw the curtains and they did what they were doing in plain view of the window. Had hey drawn their curtains they would have an expectation of privacy.

I don't really think the two-party consent laws will defend them against this recording. No one in that room had an expectation of privacy.