You were right. Polar bear Poch stands in Happyville (Original), but the Quest Log, the World Map button and the finder arrow were all sending you to plain Happyville. All three now point to Happyville (Original), and the arrow leads you to the Dimensional Mirror row of that name. To re-test: with Polar Bear Pooch's Super Snowboard ready to turn in, open the Quest Log and check the "Turn in now" line and the WORLD MAP button.