[Aldgazar]

This image is definitely from this year's animation. If you look to the right side just above halfway, you can see one of the audience members from previous year's animations. (should look like a blue blob with yellow hair, you can sort of see the hand too)

I don't think that it's a coincidence that we see a stoplight in both images either. Combined with the hint about multiple colors at last year's championships, I think that having the stoplight in the game is a reasonable assumption.

As for the diamond plate with the 5. Your guess is as good as mine.