Found the whole thing that includes when they are walking out on stage: https://www.youtube.com/watch?v=jgod-nqFEEc

Edit: There was a bit of hot mic somewhere nearby so you could hear a little bit before he sat down:

RS: “Hi Mister Trump, just take a seat over there, thank you.”
DT: “Uh, how are you? How are you?”
RS: “Good”

Music dies and mic turns on:

RS: “Mr President, we so appreciate you giving us an hour of your time. I want to start by addressing the elephant in the room, sir. A lot of people did not think that it was appropriate for you to be here today. You have pushed false claims about some of your rivals from Nikki Haley to former President Barack Obama saying…”