Not sure I follow, are people doing their own installs based on a provided 'assisted install' file?
If so, wouldn't a network install be better? That way you'd have more control.
If you want to re-enforce some settings you could use a Windows logon script to set the registry like you want it and then set the user's security policy so that they can't edit the registry.
In this case some users are installing with a provided AI file and a network install becomes difficult.
In this case there is not full control of the user machines, BYOD. The number of people who would bother with changes to the AI file is limited, but need to track if it happens.
Sounds like the short answer is that this is not possible.
wouldn't a network install be better? That way you'd have more control.
Looking at ways to setup a package that will mount a remote volume for the install. This might be the best idea as I can control read/write privileges on the network volume. Not sure if there would be control of the user copying the files on the network volume to the local machine where they have access.
If this Windows, you could do send event (or a plugin) to dump the relevant part of the registry where the FM prefs are stored, and import that into FM to report back to you.