I could be wrong, but I thought the glass itself was tinted, rather than just a surface treatment; in which case the scratch may just be catching the light and giving the silvery appearance.
It is possible to polish scratches out to some degree. When I bought a new car there were some scratches on the windows and the dealer sent a specialist out to polish them out, and the end result was satisfactory.
Alternatively you could try polishing them out yourself, a Google throws up lots of hits including Youtube videos. I've used toothpaste to remove scratches, but not on glass - yet.
If the tinting is a surface treatment then you will have to try the marker pen trick as suggested above. Another trick is to use black shoe polish - not the waxy stuff, but the liquid stuff that comes in a plastic bottle with a sponge on the top.