For the ride back to MCO, regardless of using DME, you can use resort check in and they will send your bags to the airport. We do this all the time when we have a car rental. Get our boarding pass and drop the luggage off. I believe it must be dropped out at least 3 hours prior to your flight and are open from 5:00 am to 1:00 pm.
We have never sent luggage without having anyone one the bus. A few years back, we did have a few of our of party get a rental car so not everyone was on board.