How to display results from a data table with an encrypted user id?

The plugin now works as I would like, with a little alteration. Instead of setting submitter_id to a random value, it is now set to the logged in user’s id. This will allow displaying other users’ answers. The + indicates new lines of code in the output_quiz.php file:

function wpss_getQuiz($quiz_id){
  global $wpdb;    
 + global $current_user; get_currentuserinfo();

<input type="hidden" name="quiz_id" value="'.$quiz['id'].'" />  
      +  <input type="hidden" name="submitter_id" value="'.$current_user->ID.'" />';

Thanks to Johannes Pille for the suggestion.