Can you still catch the bus and take it to the hotel from the mall? Where do you catch it and do you have to be a guest at the hotel to ride it?

It's walking distance, no bus needed

There is parking all around the Opry Mills Mall. One section of the parking lot places you in between the Mall and the Gaylord Opry Hotel. It is a short walk to get to either of them once parked.

The mall is walking distance to the motel.

Yes, but the bus doesn't come that often, unless the weather is bad or you're unable to physically, faster to walk. Bus makes several stops, one is definitely by the fuse sports bar/ big fireplace/ alternative lobby, anyone can ride even non guests.