Why did I not get Hughes's pack with the deluxe edition?

Is this happening on the account the game was purchased on? If you're playing on multiple accounts, only the one that made the purchase gets the pre-order content. If that's true, you'll need to open a case with an advisor so they can investigate this. Cases can be opened by following the steps here.

That was never stated anywhere in any promotional material and still advertised after that date. This is clearly consumer unfriendly.