Do you not understand the difference between official and third party content, Victor? Official doesn't mean "It's in the Player's Handbook". It means it was published by the main company.
Kineticists are official content. They were published by Paizo themselves.
The links you shared are not published by WotC. I have no familiarity with the companies in question, for all I know they might as well be random guys on the internet, just one step up from an anonymous page on DanDwiki.
If Larian were to include any of the content you linked there would be licensing issues. I'm not qualified to say to what extent. But suffice to say it would be easier to just ask Larian to create their own version of the class.
Oh, and by the way? Neverwinter, being an mmo, has more in common with the original Neverwinter game than either of the NwN games do.
