Thank you for the reply. When I tried again this morning, doing the exact same steps (our build server failed, along with manual processes) and everything started working. So I will chalk this up as an issue on the Azure side yesterday since it was across user accounts, subscriptions, regions and tool chains. The same exact steps that failed yesterday are now working today.
So, we can consider this resolved. It is unfortunate we don't know what truly happened, and I still have zombie Notification Hub Namespaces that I can't delete (since they were corrupted during the creation process it seems). I delete them, and within 5 or so minutes they reappear. I delete the resource group they are part of, and they and the resource group reappear. I've tried deleting from CLI and Portal with same result. Oh well, that is less of a concern.