Hi @Marc Thornton - IT Server & Cloud Engineer ,
Welcome to Q&A forum!
As of now, the Cross-Tenant SharePoint migration feature is still in private preview and there is no information available regarding when it will be available for public preview.
Due to the limited information we can find, it is not possible to test and reproduce this issue at this time.
To help you better, we recommend you directly create a support ticket from Microsoft 365 Admin Center. The support team over there has the correct escalation channel, they can involve more resource and investigate the behavior from back end as fast as possible. They also can check the behavior on your end remotely. For reference: Get support - Microsoft 365 admin | Microsoft Docs, you can select online support or phone support to have a live chat with the support engineers.
Good day!
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