I guess I'm out of the loop, but I happened to be chatting with
CoffeeTraveler and mentioned I was at Aria Las Vegas, and he tipped me off to the Sapphire Lounge pop-up that apparently opened today! And will be here a couple months according to overheard conversation with an employee
https://media.chase.com/news/chase-sapphire-lounge-by-the-club
The lounge is next to Din Tai Fung. Apparently seats ~40 pax. Small area in front where the bar and snacks are with seating for ~9 people, and slightly larger area in back with a DJ station and sorta Centurion JFK speakeasy vibes.
Wild Card:
Kimbap and katsu sando are fantastic: