We a bit more mess here. According to this code, all parameters have default values, so theoretically code like {{ ez_render_field( content, 'location' ) }} should work, but it throws an exception about missing params. So minimal set of parameters for ezgmaplocation filed type is {{ ez_render_field( content, 'location', {'template': _self,'parameters': {'width': '100%', 'height': '330px', 'showMap': true}}) }}
But I won't fix it here. I will simplify the check for showMap and showInfo only.