@Enterprise Architect， Thanks for posting in Q&A.
For Autopilot registration, there are the following ways:
- OEM registration
- Reseller, distributor, or partner registration
- Automatic registration
- Manual registration
If the device you bought contain the Autopilot service, then OEM, Reseller, distributor or partner will help to do the registration. However, if the device doesn't contain the Autopilot service, we need to manually collect the hardware hash. You can do it via PowerShell script in the following link:
To deploy hybrid Azure AD-joined devices by using Intune and Windows Autopilot, we can refer to the steps in the following link:
As a note, this method needs the devices in office network, and it needs to access Active Directory domain controller.
For the MDM discovery and compliance URL, it is under automatic enrollment MDM user scope. If the automatic enrollment is configured, then the URL will be get automatically.
From the information you provided, I notice the on-premise domain and Azure AD tenant use different name. Please confirm if your domain is routable. If not, you can add the new UPN suffix as a workaround. Here is a link with more details for the refence:
Hope it can help.
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