You have to add keys under:
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\DeviceInstall\Restrictions
The keys I have right now are all REG_SZ (strings), and in order of "1" through "5", are:
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1. SWC\VEN_DELL&DEV_AWCC
2. SWC\VID_DELL&PID_AWCC
3. SWC\Alienware_Command_Center
4. SWC\AWCC
5. SWC\VID001&PID0001&AWCCWINUI3APP
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Nothing short of this prevented "Alienware Command Center" (AWCC.exe) from pushing itself onto my machine because of my Alienware OLED monitor.
I should note it's possible to shoot yourself in the foot there; I had entries 6, 7, and 8 blocking SWC\Generic, SWD\GenericRaw, and SWD\Generic — and that prevented Audio Endpoints from being mounted...