One you’ve enabled remote management using the server manager tool you should head over to the command line and run this command:
reg add HKLM\Software\Policies\Microsoft\Windows\DeviceInstall\Settings /v AllowRemoteRPC /t reg_dword /d 1
This command enables remote access to the device manager. Please note the while you will have the ability to view the device manager you will only have read-only access to it. I am assuming the reason for read-only remote access to the device manager is for security concerns.