We are having the same issue.

I have done a little more testing and have found that either an inplace upgrade or imaging the PC from SCCM TS still does not work. But taking the ISO and installing it as a fresh install on a PC works fine.

The issue is that it just does not enable or see the site list. It does not matter if it is enabled by GPO or by the registry keys. I can see the Enterprise Mode option in the tools menu, but clicking on it does nothing. If i enable it from the developer tools, the icon for EM shows up and is displaying the site in the emulated mode, but once i close the tools it does not work.

Edit: We are also using windows 10 enterprise.