ROSEY P - I don't know of a cure for scorching, but a garment I was pressing on a wood clapper picked up some color from the wood. I soaked it in Biz for a couple hours, then washed it, and it was fine. Biz has enzymes as its active ingredient, and more than one sewer suggested it. It's worth a try with the scorch marks, since you have nothing to lose.
Oxy-Clean might also be worth a try. Its active ingredient is a non-chlorine bleach, like the old Snowy bleach. Soaking for a few hours . . .
But I can't say which to try first.
LAVINIA - I suggest one of the 80%cotton/20%poly battings for your friend. The only quilt I ever made with poly batting, my first, sits on a quilt rack and I never use it. It doesn't breathe the way cotton does, so I was either too hot or too cold with it on the bed. Mostly too cold. JMO
I think the needle-punched battings like Quilters Dream would hold up better to multiple washings & dryings than the Hobbs Heirloom, but your friend probably won't be laundering it very often. The needlepunched battings don't have to be quilted quite as closely, either.