Jim, thanks so much for the first hand information and the links to more good information.
“I couldn’t figure out how to get exact geographic coordinates which could be tricky in areas where the map doesn’t show much detail.”
For gps navigation I’m using the Avenza app with detailed maps. At the bottom of the screen there are exact coordinates for one’s location that are easy to copy and paste so there are no errors. They can be set to read out in various lat/lon, utm and a couple more formats. So those readings can be relayed but doesn’t the satellite connectivity relay those to emergency services automatically or does the user need to do that?