Just opening this for discussion.
This module uses geoPHP (1.2), which seems abandoned. At least, there's no activity in its repo on https://github.com/phayes/geoPHP
This gets more urgent, as PHP versions move on.
There are forks, here's a discussion. Note the fork by @itamair, which already includes several fixes relevant for us: https://github.com/itamair/geoPHP
So the question is: should we switch to that version at some point?