Buy a can of "Spray and Wash," now renamed "Resolve," and a box of Biz powder. (Get the aerosol, not the pump refill.) Spray the fabric, let it set for 10 minutes or so, then soak it in Biz dissolved in enough warm water to cover it. The soaking might take a day or two. Slosh (move) the quilt around in the Biz water a few times a day. When I taught school, I got ballpoint ink on my clothes daily, and it always came out using those products.