We've stayed at Two Rivers 2 or 3 times, we like it there. We've used the shuttle each time and greatly enjoyed it, sure beats wasting time looking for parking!
I would think IF the shuttles are running there would be some safe guards in place to keep customers safe. Easy way to find out, call Two Rivers or the shuttles people and ask what if any CIOVID procedures are being practiced. I'd be more concerned with the HUGE crowds downtown myself! :E