Managed Devices for Guestuser

Hi all,

we want to combine the advantages of guest users and managed android devices.
Guest users for data protection (e.g. prevent GAL viewing).
Managed Devices for the management of our devices that we issue to guest users.

We have integrated Managed Google Play for Apps and devices.

As I have to determine, I can't assign devices to a guest user, even though the Intune license has been granted. Even if I make the guest user to a member afterwards.
On the other hand, I can assign devices to a member user whom I have subsequently demoted to a guest. Unfortunately, the user can view and resolve users in GAL, which a guest user should not be allowed to do.

What is the advantage of the User Type change, if a member becomes a guest but still has the advantages of a member?

Is there a way to assign managed andorid devices to guest users?

Regards

Viktor