Just off the top of my head, I'd credit "others" as you have suggested. I've read so many posts here about quilts that have been discovered at estate sales, yard sales, Goodwill and various other places that weren't labeled and left the purchaser wondering. Any information on the labels is an important part of the history and making of the quilt, regardless of who inherits it. It's only right to give credit due to whoever helped make the completed project, even if you don't have the actual name. IMHO only.