You can put some polish (I use Flitz, and know nothing of Barkeeper's Friend) on a piece of ribbon and work that between the scales to get the yuck out. Some people use dental floss around the pins. The same polish will freshen up the blade. I don't know if it will remove the patina, but it will make the patina more shiny. It's fine for use on the outsides of the scales, too. I use paper towel for polishing, NEVER a Dremel.
Post a picture so we can see how it cleans up.
Best wishes.