I’m not sure how far you’ve got with this but this works for me.
acf.add_action('google_map_init', function( map, marker, $field ){
// map (object) google map object returned by the google.maps.Map() function
// marker (object) marker object returned by the google.maps.Marker() function
// $field (jQuery) field element
var autocomplete = new google.maps.places.Autocomplete( $field.find('.search')[0] );
autocomplete.addListener('place_changed', function(e) {
var place = autocomplete.getPlace();
// your code here...
});
});