To begin with, I would never had used the blocks and made new blocks. There is way to much time and money put into a quilt to piece blocks together with cuts in them.
A picture would have been helpful to see where the cuts where.
After a quilt has already been quilted its hard to repair it and not make the repair look like a repair. Not sure if fraycheck would help, worth a try. Maybe applique? More than likely these cuts will continue to get larger everytime the quilt is washed no matter what is done. Live and learn, when cutting fabric never have finished blocks or other fabrics anywhere near the rotary cutter. :cry: