FlintlockJazz: My guess is that they either had a problem with the quest log updating (since most people would have nekker parts by then anyway they realised it would skip the pig stage completely) or that it possibly contradicted with the lore. Remember, the wraith said that the dead cannot be lied to, so maybe they found out later that tricking him like that went against something pre-established by Sapkowski, and decided to stay close to the lore (instead of other companies that change lore based on who has been sucking them off in the office the most).
olimikrig: You can lie to the dead just fine. In chapter 2 (Iorveth) there's a certain ghost you can trick into believing you were a member of it's unit.
Good point, in that case they probably just took it out for the aforementioned people already having the nekker parts and it updating automatically. It fits with the other things that are different in the walkhrough (the fisstech gang being one).
Bossasianmafia: It's a bug. If you check your inventory after the conversation with the 2 guys, you'll realize that you'll be GIVEN the 2 nekker parts. They are both labelled as quest items, which means you can't drop them. Regardless of whether you then go to the butcher to get the pig parts, the ghost takes the NEKKER parts rather than the pig parts.
When I did that quest with no nekker parts at all the quest did not automatically jump forward to the next step like it does if you already have the nekker parts, and the quest still pointed to the butcher for me, and I wasn't already given the parts. Maybe it was different for you but I guess it actually transformed the quest nekker eyes and hearts from the body parts you have already harvested from them.
Tracido: Exactly Flint, not to mention there are several of those incorrect references I've seen myself, I simply tried it myself because I was simply trying to work around the lack of an option & thought the guide might have been correct.
Indeed, the fisstech gang option is when I first realised that the walkthrough wasn't 100% correct. In the walkthrough **SPOILERS** it says that if you had the real recipe then you get released automatically and don't get the option to fight your way free like you do if you give the fake one instead. Ingame however you get the option to fight free whether you gave a fake or the genuine one. The manual lists different talent scores than the game shows and claims that you can have two mutagen slots if you put two points in the ability when you actually can only put on mutagen on whether it has one or two points spent on it (at least that's what I've found anyway).