WOW, three years at a longarmer that is unimaginable to me. Course I do my own quilting but honestly what's going on with that person that it would sit there for three years?
Personally, I have never seen an unfinished quilt at a show. As in your case for demos, trunk shows and lectures that would seem fine. Since you are to be the featured quilter I can only think your work must be fabulous. But judging at shows is a different story altogether. They are looking at the finished product to make their decisions regardless of who did the final quilting.
I would get in touch with your guild and find out what requirements they have to show your quilt. There are different rules for different guilds and shows. So that would be the first place to start.