I don't think you could ever get the whites to match if you try to fill the scratch with something.
Could you find a pretty sticker to paste over the scratch? Maybe a vinyl decal like this one (cut to size, of course);
http://www.amazon.com/Removable-Saku...dp/B00E8AUS2I/
If the scratch is too deep for a decal, you could fill in the scratch with something like white Elmer's glue (that dries transparent) and place the decal or sticker over that.