Answer is simple: Photoshop
About color of concoctions: I don't remember Sapkowski describing specifically any potion color in the books, so I don't see why CDP shouldn't decide which to give. It's just a matter of reference.
I.e. Swallow is the potion to regenerate HP, meaning life, that in any fantasy game is associate with red (--> blood, even in our real world it is so). That's how they maybe decided to give it that color instead than blue as it used to be, that should be instead associate with mana, i.e. energy.
That's my guess.
No idea what W3 White raffard color would be, but I don't see the problem to be honest.
Wouldn't you play the game the same if White Raffard would be purple or green or anything? I would to be honest.