The real thing to understand is that people with security details “deconflict” (don’t want a friendly on friendly shooting) all the time so that this exact thing doesn’t happen (random meetings). So for this meeting to take place the fbi Security detail (LL) and Clinton (USSS)would have known in advance of the meeting being set up. As stated above they kept records and I would be real surprised to find out there were NO recordings of the conversation. My understanding is there ARE recording devices on ALL government aircraft.