The Mechanics' Institute Chess Club has been verified by Chess.com and is eligible to run cash prize events.
Official Chess.com Prize Tournament Verification

Chess.com will review all the games from our event within 72 hours and we are also having Dr. Ken Regan from University of Buffalo, a world leader in this area, also run all the games through his algorithm for fair play violations.
This will be weekend of May 30, 31. Rapid 30th, Blitz 31st
Ok, this sounds great. Investigation and analysis, can't ask for much more. USCF member and fee to play?

Correct, since it is USCF online rated.
https://www.milibrary.org/chess-tournaments/2020-mechanics-institute-rapid-blitz-online-championship