Or whichever place has it for sale in an all-in-one-all-inclusive-everything-you-could-possibly-want-all-together-in-the-one-package version for a few quid. Steam always has a sale anyway, so I assume anything I bought in a sale was from Steam. I so rarely touch EA Origin or Uplay and hardly ever find Humble/GoG games these days either...
But I really don't care who has it on sale or whether it's exclusive or not... I care about not paying £70 for half of a £10 game and being forced to pay stupid money for the DLC that should have been included in the first place.
I must sincerely apologise to you and your people, for my offensively gross negligence in mis-stating the exact, precise source of my discounted sales items and shall make appropriate amendments to my original post whenever I can be bothered...