Vintage best Peach Applique Quilt

This is a beautiful vintage appliqued quilt. The main colors are peach and white with appliqued flowers of blue, green, and purple. It measures 72" wide X 88" long. Unfortunately I gave it to my daughter about a year ago and not sure what she did, but somehow all those black marks appeared (see photos). I washed it, but not sure how to remove those stains or what they are; therefore it it sold in "as is" condition. The quilt best itself is in very good shape and has beautiful quilting. It still has a lot of life in it and could be used or displayed.