Vanilla 1.1.5a is a product of Lussumo. More Information: Documentation, Community Support.
Chris,
Unfortunately, it looks like you have encountered a bug in your game. You were supposed to use the card key way back in Arizona to enter the fort, at which point it should have been removed from your inventory.
We have 2 options here. You can create a new profile from the main menu and begin again, and likely will not see this bug again, or you can contact us at support@mumbojumbo.com to assist you in a work-around.
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