@Rick Juab
Thank you for your post and I apologize for the delayed response!
Based off your issue, you should be able to leverage LDAP synchronization with Azure Active Directory (this has a cloud web app). This feature leverages AzureAD Connect rather than AzureAD Domain Services, but is used when you need to synchronize identity data between your on-premises LDAP v3 directories and Azure AD.
For more info - https://learn.microsoft.com/en-us/azure/active-directory/fundamentals/sync-ldap#use-when
I know you mentioned that you aren't talking about user authentication. However, the only article I found that leverages AzureAD Domain Services (AD DS) is our LDAP authentication with Azure Active Directory.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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