Hi Geoff,
There is a similar thread on this at https://answers.microsoft.com/en-us/msoffice/forum/all/how-do-i-setup-azure-maps-to-get-sharepoint-online/07abc131-0295-4ec7-a4da-708eb7d95217. Also, yes, Bing Maps for Enterprise is being replaced by Azure Maps as per https://azure.microsoft.com/en-us/blog/azure-maps-reimagining-location-services-with-cloud-and-ai-innovation/ You can't create a new Bing Maps for Enterprise account as of last June and all of the free accounts will end this June.
Have you followed up with Sharepoint Support on their plans for migration? I think you can also leave feedback against their documentation as well.
Sincerely,
IoTGirl