Granite repair?

We recently replaced our old formica countertops with granite. The old counter and sidesplash had a squared edge which was cut slightly into the door frame leading into another room. Obviously, the new rounded edge of the granite would not fit into the old square cut. Well.... when I wasn't in the room, my husband told the installer to cut the granite to fit because he didn't want to replace the door trim. Now I have granite that is bullnosed up until the last 3/4" on the end and then it's squared off to fit into the old cut in the door trim! I want the end to be rounded off (and polished) like the rest of it but I'm not sure if this can be done. Is it possible to just round off and polish that little piece on site or would the whole 2' x 2' piece have to be removed and sent in to be done? It is such a small piece - really it's just a chip of granite.

Thanks!