Greetings,

I'm trying to understand the issue you're having so I can assist. You mentioned you bought the "digital version" of Heavensward from GameStop? I don't believe that GameStop sells the digital version of the game as that is currently only available directly on the PlayStation Network.

The instructions you linked to were for users that purchased directly from PlayStation Network. Those users will not receive a code to enter on PSN because it's already tied on the back end.

Users who buy the physical version from GameStop will have a code inside the sealed game case (12-digits) that they will need to redeem on PSN. Here are instructions for doing that: http://sqex.to/Bdc. After the code has been redeemed, the next time you launch FFXIV, you will receive the prompt to tie it your service account.

Hopefully this clarifies things a bit, but if not, please let me know more details!