Oh no! I know that feeling - I did nearly the same thing. On my own project, at least, but one that I was rushing to finish (always happens when you're rushing!) and I felt just sick to my stomach. I ended up being able to mostly fix it but it wasn't as good as the original job had been, sigh! You did a great job fixing this mistake, nobody will ever know it was there except you two, and might even make the quilt that much more special to your friend because it has a little hidden, secret story to it! Thank goodness it was a scrappy quilt and not something that you had to try to find out-of-print fabric for or something!