Yes, you can (at least for Android, not sure how Windows behaves), if the user connecting, is NOT part of the Mobicontrol administrators role.

1. Goto users and permissions
2. select the relevant role or user
3. device group permissions
4. select relevant group
5. scroll down to remote control devices in permissions column
6. uncheck the last option "control wtihout notification"
7. redo step 4-6 for every group needed
8. redo step 2-7 for every role/user needed

If done so, the user should need an accepted prompt to get remote access for any device in the selected group.