The PnP-Monitor Lock (Standard) driver does not now allow the monitor to appear in the color management device list (Win10 Pro 1909 and 2004). I'm sure it did until a week or so ago, so something in Win10 has changed quite recently to prevent it. The result is ICC/ICM color profiles cannot be applied, the fix is to uninstall the PnP-Monitor Lock (Standard) driver and use the generic PnP monitor one instead. This is unfortunate if you want to blank the monitor when remotely accessed and use colour profiles.
Yes, this was a known issue caused by the Monitor Driver that occurred in older versions preceding our latest release of the 188.8.131.52 Beta 2 version. We've discontinued the Monitor Driver in our latest release and replaced it with another screen blanking mechanism that also supports custom text for the blanked screen.
In addition, please also note that I've replied to your message in this thread.