To decrypt AES you need some sort of a secret key or certificate. So the game will have to have it bundled.
If the Dev were to take, for example the x,y position of the player and convert that to a key, then there would not be any bundled key. This could allow specific conditions to be met without specifying the key or solution. Truthfully though, I don’t know much about AES to know if that’s possible.
Funnily enough, when I go to a restaurant and they have receipts with QR codes (I think it’s Clover), it just doesn’t work in Firefox.