I did a little more work on the cabinet tonight and discovered that the escutcheon hole was packed with wood filler.
It seems unlikely this escutcheon originally went with this cabinet - or at least this center board.
It came out easily and the old finish just melted off with CitriStrip.
It should be a piece of cake to refinish. Mohawk Medium Walnut on the center board and Extra Dark Walnut on the rest.