Tell her all the ways (suggested above) to fix the problem and ask her which one she wants. If she is not aware of the problem, she will keep making the same mistake time after time.
Let her know that machine quilting on a frame is different from hand quilting or tying a quilt and a lot less forgiving.
Also, if she redoes the borders, she needs to put the longer (border or pieced top) on the bottom so the feed dogs will help.