If you want to add additional roles to your Vibrant administrators, you can simply add them via /configure-adminaccess add. The role will immediately be able to use any of the /configure-… commands, provided you have also given them command permissions.
If a user reports that they cannot use the administrative commands even though you have their role assigned as administrator, make sure they also have the Discord-based command permissions. Go to Server Settings ➡ Integrations ➡ Vibrant Community System and find the commands they need access to. In that User Interface, you can now enable their individual permissions based on the role they have.
The Discord role you want to give administrator privileges to.