Hello Justin Marsh,
Thank you for reaching out to Microsoft Support!
After testing, it turns out to be true, as you stated, that when using this endpoint, if you do not have the global administrator role, a 500 error will be reported and you need to grant RecordsManagement.Read.All permission and have global administrator role to successfully access the endpoint.
Therefore, the issue may be internal to that endpoint and you are advised to submit a user voice for this or open a support ticket. In the meantime, if you don't mind, grant the global administrator role to continue to access the endpoint until the issue is fixed.
Hope this helps.
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