Hi @Chad Scott
Using list subscribedSkus only you can get the list of commercial subscriptions that an organization has acquired. I have tried to replicate the same scenario but it's working as expected.
I would recommend you to raise a support case with Microsoft Graph, a Support Engineer will be able to assist you better. You can raise support ticket from
http://aad.portal.azure.com/ or https://admin.microsoft.com/#/support/requests.
Hope this helps.
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