I don't think goose down has ever been used in quilts. It is used in duvets. Maybe she wants you to make a duvet cover for a down comforter?
As far as I know, there is no such thing as goose down batting. Cotton batting, polyester batting, bamboo batting, silk batting, wool batting, yes! Not goose down (or duck down, for that matter). Comforters made with down are always made commercially because there is such a control problem with handling down.