@Vedanth Pulipati
Thank you for your post!
Adding onto what @Azure Engineer mentioned, OUs don't show up using the Microsoft Graph API or in the Azure AD UI; they're only available in your managed domain. For more info. Therefore, the use of Azure CLI won't be possible when trying to validate the OU structure in Active Directory. However, you should be able to use the Active Directory Administrative Tools within the Active Directory Administrative Center to view, edit, and create resources in a managed domain, including OUs.
Additional Links:
Custom OU considerations and limitations
How to Manage OUs in Active Directory
I've also added the windows-active-directory tag to this thread so their community can take a look into this as well.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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