Alright you can get the rewards for the charcoal game by just simply passing the levels you don't have to get silver at least from what I see on my end, the Ribbie companion is pretty awesome, and you can get it after finishing the 4th round. It's probably worth playing for that since its pretty easy to get, I am not a very accomplished gamer and I got it.
I am not sure what the reward is for getting all silver or above.
I am not sure what the reward is for getting all silver or above.