Thank you for your suggestion. I am on GSS 3.2.
Yesterday, I had another thought before leaving the offfice. I compared my lab enviroment to the production server. The only difference I spot was ADK version. In production I had newer version than in lab. After installing the 10.0.10240.0 version it worked like a charm.
Here I found very nicely listed all Windows 10 ADK versions.
http://renshollanders.nl/2016/12/download-windows-adk-the-numerous-versions-of-microsoft-windows-adk-assessment-and-planning-toolkit-and-where-to-find-them/
Here you can find the GSS matrix support.
https://support.symantec.com/en_US/article.HOWTO111528.html?
I wish I did not spend that many days troubleshooting it.