Wow, what an interesting thread. I have only had this problem when I use a really loose woven fabric. In the old days, back in the 70's, when it wasn't totally clear what fabric to use for quilting, I did have a problem. Usually I found washing and drying the fabric tightened the weave (more or less). Some tightened more than others and some didn't tighten at all. On my second quilt that I made, I had some problems of seams splitting apart. The fabric had to be really awful, as at that time, I was sewing 5/8" seams. It wasn't until some time later in the 80's that I started using 1/4" seams.
I would definitely contact the manufacture about this problem. If they don't know that a problem has occurred, they can't fix it and they can't compensate you, either. There may be others in the same boat with this fabric problem for that run of fabric.