I pre ordered the Super Deluxe edition via the Microsoft store on XB1, and was also missing the skins and other pre order bonuses. When the game downloaded it didn’t install the pre order bonuses. For whatever reason, it only installed the 2 bonuses that were listed under the super deluxe version. So you have to go to the Deluxe version page and manually install each bonus. When you click on them they say “you own this product” and you have to then click “install”. Once they are all installed, they will show up in your in-game email and you can accept them.
As for the gold weapon skins pack, that one I googled and found my way to the Microsoft store online on the base game page, and sure enough, there was the pre order gold weapon skin bonus. I signed in and was able to add it to my install list on my xbox.
Hope this helps everyone, cause I know I was rather frustrated by the missing content. Oh, and FYI, the weapons and grenade mods will redeem at your current level, so wait to “accept” them until you’re at the level you want them to be.