@Henrik Lindgaard Thanks for posting in our Q&A.
For our issue, I have done some research. But I saw in an article that the Directory where the TaskbarGlomLevel key is located should be
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
Please refer to: https://www.tldevtech.com/how-to-disable-taskbar-button-grouping-in-windows-10/#:~:text=%20The%20following%20steps%20are%20needed%3A%20%201,In%20Windows%2010%2C%202%20means%20Never.%20More%20
Note: unofficial link, just for reference.
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