So I tried Edge on Windows, same result. It got weird when I tried Firefox on the Pi. Appeared to be same result, but then I checked the sensor reading on my phone at the end of the day and it had stopped updating.
When I installed Firefox onto the Pi, the SG3 system disconnected from the sensor. It took uninstalling Firefox and a reboot of both the Pi and extender to resolve. Going to do a little more testing with rebooting with FF still installed, but it seems like Firefox might interfere with the SG3 programs.