I am using RichMarker for Google Maps v3 as found at https://googlemaps.github.io/js-rich-marker/reference.html
I have successfully been able to register clicking on
google.maps.event.addListener(richMarker, 'click', function(event)
{
// your stuff here
event.preventDefault();
event.stopPropagation();
event.preventDefault();
});
You'll need to modify the library.
Find this part:
google.maps.event.addDomListener(this.markerContent_, 'click', function(e) {
google.maps.event.trigger(that, 'click');
});
and change it to
google.maps.event.addDomListener(this.markerContent_, 'click', function(e) {
e.stopPropagation();
google.maps.event.trigger(that, 'click');
});