Amazon and Gamestop pre order DLC question

So Amazon and gamestop are having different pre order DLC’s for a game I want. I was wondering would gamestop allow me to return the game unopened if I used the DLC code? Or am I able to get the Amazon pre order code and cancel my order? I have never pre ordered from amazon and don’t know how it works.

Gamestop requires the games to be opened before you return them.

Amazon normally emails you the DLC codes before release so you can just cancel the order. If you don’t get it before release just send the game back and use the DLC code.

I have never had a problem buying a brand new game then instantly returning an unopened game for full price paid, and still keeping the code on receipt.