The security role appears to be for this solution, it's not an out of the box one. The installation guide states that it adds the role to all users on setup, but I'm not sure if it continues to add it for new users when already installed.I wouldn't think this solution can assign licences, or otherwise activate users who don't have a licence. Are you saying that these users are showing up in Dynamics 365, even without a licence assigned? That should only happen if they are an Office 365 admin (as you've stated), or if they've been set up with the access mode of "non-interactive".
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