First of all, I would provide feedback to the show. If yours has creases, do others? You enter shows often, your work has been highly showcased these are not utilitarian quilts, they are works of art and should be treated as such. Second, what type of batting did you use? If it's wool, can you use steam? You must have some contacts with other artists that enter shows like yourself, have you inquired with them for suggestions?
I have no suggestions for you, my quilts are not showing pieces, but I would research the heck out of it before doing anything so as to not ruin the show piece. Good luck, I hope you get this figured out in time to enter it in the next show. And I can't even imagine the despair you must have felt when you received your piece back and opened the package.😔