The quilt is beautiful. How big is the hole? There was a beautiful quilt posted here where the lady put a pieced back on her quilt. She had a row of small rectangles going thru the middle of the back. It looked great. You might could add some type of applique along with your patch to make it all look like it was on purpose. Could you do any hand applique on it before it is all finished so you would be able to include patches in the quilting?