Hi Ralph,
The quote from the how-to is my personal note regarding the information that i suggested to be presented there.
I’ve put this at the beginning of the How-To:
Below I’ll describe the setup steps and also the personal notes of what I think it should be added as options/features.
I know it is not optimal and that How-to needs to be re-worked. but i did not have yet the time 
…
But you are sustaining a point that I was making 
PS. Maybe it will be of help to you to try and use other registry settings for your win clients.
See here: Unable to join windows 7 client to nethserver domain - #32 by alefattorini
And here: Windows 10 join nethserver - #21 by dz00te
Also try what Stefano suggested. Add a new fresh client to that domain and see the results.
BR
Bogdan