I'm aware of how unpleasant he can be; he was well known in Poland even before the games and he was making offensive statements even then. I don't actually like him as an author. All of which is not relevant. I doubt CD Projekt were unaware of the relevant law when they made the deal. Instead of reading his interviews, read the few pieces by Polish lawyers on this; no one seems to be sure how it would play out in court. So they might just play it safe and settle, but it's got nothing to do with goodwill.
Not sure why you're so fixated on that, but I don't think he meant they were just doing it out of the goodness of their hearts.
They obviously want to keep relations positive in case they want to return to the IP for a future game. While they don't necessarily need him on their side, it would probably be beneficial.