Actually, the image is mine. And I posted it in a thread that you started!
If I didn’t expand much the my answer in this thread, it’s because I already said most of it more than an year ago…
If you choose to use OSL, you could adapt this script from Michel Anders to output all 4 values stored in the da[] array.
With nodes is a bit more complicated, but most of it is just a repetition. You might look at this old post where I do a 2d Voronoi.
Making it 3d, is just a matter to duplicate a more modern version of that nodegroup 27 times (instead of 9 of the 2d version).