Hide result shortcode until user input (ajax auto update)

Yes, you would need to edit the results.php file, as indicated here (changing the ID shown to match that of your form):

global $searchandfilter;
$sf_current_query = $searchandfilter->get(11690)->current_query();
if ((!$sf_current_query->is_filtered())&&($sf_current_query->get_search_term()=="")) {
  echo '<div>Nothing to see here folks!</div>'; 
} else {
  // the current resuts.php code here (ALL the code from the if ( $query->have_posts() ) line and onwards)
}