I believe you could make an easier pattern in the size you want before the 'deadline' or you take a photo of your progress and include it in a card with a note saying it's in the works. Don't let guilt rob you of doing what you want in your heart to do, which is make a quilt for them. Just work on it steadily. Who knows? By the grace of God, you might have most of it completed before the 8th. I was in a similar crunch mode , trying to make couch size Log cabin for my sister's 50th b'day. Lots of mistakes from rushing, but I didn't want to quit. I wanted to give it to her on her b'day (Nov) which I did, but only had the binding left. Sent it to her at Christmas, finished, and she said it was like getting another gift for Christmas!
Having said that, I've never attempted a DWR so I can't help with your questions. Just want to encourage you to follow your heart rather than the pressure of the calendar. You won't regret that.