This video may be helpful.

https://youtu.be/a-MdFDuTIws

Call her first! You may want to have her come over to see the dilemma that you are facing. Was this quilt hand pieced or machine pieced? DWR's are notorious for being out of square. I would be sure to let her know that you many not be able to correct it and keep it square using the current design option. Let us know what happens. I was just looking at another thread where a DWR has poofs throughout the top. I strongly suggested hand quilting so that she could stretch out each area in her hoop or to LA it with a bit of pull. It may be a quilt that a custom design is the only way.