Seems to be a bug as I just bought it for my friend and it came with all DLC, I just bought it for myself (I already own the game) and it gave me all DLC, for $12 its insanely good for all the new dlc's! Cheaper than even just buying the newest one (Three kingdoms) on its own!
TL:DR; Not meant to come with all DLC but does, $60+ worth of DLC.
Holy sht, it does!
Redeems as AoE II Ultimate Bundle, adds 8 DLC to my existing 4. Even better value for someone who doesn't have the base game.
Thanks, OP!