@Jonathan Tarro Thanks for posting in our Q&A. From your description, did you mean that you want to migrate some device from co-management to only configuration manager? If there is anything misunderstanding, please correct.
I noticed that you have removed these target devices from the pilot group. Please also delete these devices from intune portal.
If you don't want to see these devices in intune portal. Please close this setting "Upload to Microsoft Endpoint Manager admin center" in Configuration Manager admin console's Administration > Overview > Cloud Services > Cloud Attach.
https://learn.microsoft.com/en-us/mem/configmgr/tenant-attach/device-sync-actions#bkmk_edit
Hope it will give you some ideas.
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