I would just "give it up". I remember when I was in college and we had a Secret Santa thing in our dorm where someone had picked your name and left you a little present like a candy bar every day with a "clue" as to who they were and then on the final night's Christmas party they gave a larger present and revealed who they were. Mine turned out to be a friend, my next door neighbor in the dorm and she gave me an adorable bra and panty set so I put them on and went next door; she had a single, had the room to herself, I knocked and opened the door and. . . she wasn't there but her boyfriend was My little brain went into overdrive and I decided it looked a lot like a bikini and it wasn't like he probably hadn't seen a woman in bra and panties so I went in (left the door open, LOL) and did my best modeling for him!

I would just go up to him right away and say "hi" and do a little chit chat and see if you can't get rid of some of the awkwardness that way, try to normalize the rest of the meeting?