Red Roof Inn, definitely. :2thumbs:
From what I remember of last years event, Gatlinburg itself is fairly compact and anyplace you stay there will be reasonably close the events. Plus it is a tourist destination so there are a lot of motels in Gatlinburg. Pigeon Forge can seem pretty far away if the traffic is heavy and the entire area is a tourist trap so traffic can be heavy quite a bit of the time. There weren't any vendor displays set up last year except for Corbin bringing their trailer to the dealership that helped out with the event. If other vendors are coming and they set up at that dealership, I wouldn't worry about trying to get a motel room near there as the dealership was a little far away from the bulk of the rides and dinners.
Both the event motel (can't remember the name, docdoru is staying there) and the Red Roof Inn were great places, no complaints, last year. Try them first then try others that you can find online if those two places are booked.