I’m having the same issue, similar at least. The API keys have been entered, unrestricted, the console shows
Google Maps JavaScript API warning: NoApiKeys https://developers.google.com/maps/documentation/javascript/error-messages#no-api-keys
Yet I have them all set. According to that error, that’s an issue with the plugin, not the API key setup.
I followed the API guide to a T.
Made sure I wasn’t hitting page cache as well.