This problem has been brewing for sometime. There is no other software that processes the Nikon camera settings as recorded by the camera when the image was shot. Note that recorded value could change with each shot so a pre-set in another program may come close but it is not the same as reading and applying the settings from the camera.
Either Nikon will have to hire the Nix programmers familiar wtih Nikon Capture Nx2, find another 3rd party to write a replacement, or develop the programmers in house.
There also is the question about the source code, human readable program instructions, for Nikon Capture NX2 and special Nik features within Capture NX2.
It will take time for Nikon and Nik to sort all of this out.