This a DLC pack! It is not possible for Steamgifts to recognize DLCs on Steam accounts. Which is why the entry-button is green even if you have all the DLCs on your account.

Therefore I ask you to be sure that you do not have most of the DLCs already before entering, as to save time and effort in regard to a reroll otherwise.

If you have some of the DLCs but not others, it is ok to enter if you have 5 or less of the DLCs in the DLC-pack.