Synchronize users and passwords from LDAPS (Novell-based) to Azure Active Directory

We are a school and have a Novell/NetIQ directory service for our local computers. Multiple services (such as Moodle) are connected over Open LDAP/LDAPS (Port 636) for user authentication. We would also like to have the same usernames/passwords for Office 365. Till now, we import the usernames from a csv-file at the beginning of every school year and generate passwords directly in Office 365, but it’s confusing for our users to have different passwords for different services and it would be nice to have everywhere the same username and password.

Is there a way to synchronize the data from Novell/NetIQ (master) to Azure Active Directory? Ideally over LDAPS, because our server has already an outside connection for Moodle and other services. For historical reasons, we can not migrate to Microsoft’s Active Directory.

What I’ve tried:
Installed Microsoft Azure AD Sync on a Windows Server and tried to add a LDAP-connection referring to this source. Connection failed, "The LDAP-Server is not available."