Just for help some people, the boxes that has the PIN GRATUIT yellow sticker only offer the Atari Lynx pin not the game pin.
I recently bought the exactly Robo-Squash and Bill & Ted games with the same yellow sticker and the only pin that was inside was the Atari Lynx pin, not the Robo-Squash or Bill & Ted pin.
For get the game pin really you need to find the stickers that says: 2 Pins Gratuites, like this:
http://i.ebayimg.com/t/Robo-Squash-Atari-Lynx-Boxed-Complete-/00/s/MTE5NVgxNjAw/$(KGrHqV,!qkE-YdL(j-bBP2LgIlPg!~~60_35.JPG