I had a similar experience years ago, however, I don't remember where I bought the fabric, and of course it had to be the very first commissioned quilt. I had done a Roman Stripe pattern,and it was pretty. When my friend told me about the problem, I took it back, hashed and re-hashed how to repair the quilt, when I had an "Ah Ha" moment. I appliqued new black fabric on the blocks that had problems,then quilted over the square, to match the straight line quilting. The question I asked myself time and time again - "Why did it have to happen on my very first commissioned quilt, although after my "fix", he was happy, so that's all that counts.