Dear @Michael Veloso,
Thank you for posting your question in the Microsoft Q&A forum.
I understand that you have thoroughly attempted various workarounds, including multiple registry edits and disabling methods, on your test environment, but without success in resolving the conflict.
Currently, on my test environment, I have tried many ways to turn it off, but it still doesn't work. Therefore, in this case, I suggest you ask the Global Admin to submit a ticket and reach out directly to the Microsoft technical team, so they can investigate and see if they can provide any suggestion (because we have already done the general steps like editing the registry). I have also searched many other articles already, but I haven't found anyone sharing a solution. So, your immediate action in escalating this to Microsoft will be the most effective path forward.
Please help me ask they follow this article to submit a support ticket. Get support for Microsoft 365 for business
Looking forward to your response!
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