The best way I know to fix a cork handle is to get some old corks (or new.. doesn't matter) and then crush them up... be creative.. use a meat tenderizer.. a ballpeen hammer.. whatever... just get them good and crushed up... after they are crushed up to a nice pebbly consistency (maybe 1/16" diameter pieces) Next get some Titebond or an equally good brand of carpenters glue.
Mix the cork crumble and a good measure of glue together on a piece of waxpaper or aluminum foil, forming a nice loose paste.
Sand your cork handle with some 200 - 300 grit paper to remove and dirt or grease. Take your fingers or a butter knife (or Popsicle sticks if you have them) and put the past cork mixture into the holes on your cork handle. Press it in good and pile the mixture up a bit higher than the rest of the surface of the handle.
Let this dry for a while. I'd say over night is best. After it's dried, Sand it down with 100 - 150 grit paper to get it even with the rest of the handle's surface height then go over the whole handle with 200 - 300 grit to smooth it all out.
If done properly only YOU will be able to tell where the hole once was. It will look nearly good as new