Can't Access WIN 11 Desktop - "no available desktops"

I am using Zerotier on a WIN 10 PC trying to access a remote PC using WIN 11. I was able to connect and use Nomachine to access the desktop - briefly. I rebooted the remote PC and now I can PING it and see it is online, but can’t access the Desktop using NoMachine.

I know the Monitor on the remote PC is currently turned OFF. Is that an issue? Is it possible that rebooting with the Monitor OFF means there is no “desktop” to see? If that was the case, would it also be impossible to access the Desktop of a PC that had “blanked” its monitor?

The Network screen shows that the remote PC has been active in the past minute.