@TechQ, Thanks for posting in Q&A.
According to your description, I know that you cannot get the MDM server option in ABM.
From your description, I know that you are doing ADE enrollment and you have got the token to connect to Intune and sync it. And then you should assign the device purchased from ABM to the Apple token, after that the device will automatically sync to Intune, you can view the device in Intune and create and assign enrollment profile.
Enroll iOS/iPadOS devices with Apple ADE - Microsoft Intune | Microsoft Learn
For the missing feature in ABM, as it is related to Apple, we suggest that you ask help for Apple support.
Thanks for your kind understanding.
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