I am not sure but if you quilt the quilt with a quite dense but uniform quilt stitching overall you may be able to control the different amount of shrinkage on the quilt from all the different types of materials. If you quilt quite close, the stitching will only allow the fabric to shrink so far. That's what I would try rather than taking everthing apart and rewashing, resizing,recutting and sewing all those pieces again.