I doubt nvidia would have complied with their demands anyway, but the new demand "make all your code open source or else we'll release it ourselves" gives them absolutely no incentive to comply at all. If the choices are you can have your source out there but unlicensed so it's illegal for anyone else to use it, or you can choose to legally let anyone else use your source -- why would nvidia ever choose the latter?
The original version of the demand at least gave nvidia some business incentive to comply. I don't think they've thought through their demands very well.