Unattended session download from URL
In our line of business, we cooperating with our client's IT department or external consultants to setup the unattended sessions. We are usually generating a customer specific session package each time, where we fill in customer info into the session properties (Customername/CustomerNO/Etc). After generating the session, we send the installer package by email to the external consulting and they are installing it. This is very time consuming and manual.
Have you checked out the extensions that you can add to allow people to download an unattended installer from your ScreenConnect portal? You can password-protect the download option. You could provide a link to your portal and the password via email