Presumably your database contains some info that can be fed into google maps to produce the required display? Ultimately, that info will be translated into a URL (e.g.
https://www.google.com/maps/@45,5,15z?hl=en, where 45 is the latitude, 5 is the longitude and 15 is the zoom level or as
https://www.google.com/maps/place/ followed by an address is the required format). If so, you would run your mailmerge and output the URL as a hyperlink. Post-merge, you could then run a macro (maybe not even needing the google API) to retrieve the web page display for each URL and insert it with or instead of the URL. I have no experience with retrieving google maps web pages, but you may be able to dig up some code to do so via a web search.