Well I read all your suggestions and decided I wasn't good enough to take the square out, so I took out the quilting stitches and cut another square of the same fabric. I centered as best I could and pinned. I then requilted, and turned under by hand. Then machine sewed over that.
None of you would probably do that, but I did it. Here are the results.
By the way that horrible blue chalk did not come out when I washed it. I will never use it again.