I would not doubt that they would have an audio tape of this conversation if it took place in the White House.
“ This was the first ‘all hands’ [staff meeting] where they got to see Trump’s national security team”
Sounds like there were many people in this staff meeting. These 2 were attendees- just commenting between each other while listening. I doubt it was caught on tape as the focus was on who was speaking to them and the rest of the attendees. .