Execution failed: TypeError: Cannot find function getResponseForItem in object

I am hoping for some help with the following instructions I was trying to use with the Google add-on Form Notifications. I followed the directions on this page: https://developers.google.com/apps-script/quickstart/forms-add-on#set_it_up

I was positive I had copied and pasted the code right and did the test. I was able to get the Form Submission Email Notification just fine and it works, but when I tried testing the Respondent Email Notification by submitting the form with my own email address I did not get the Respondent Email Notification.

When I run the Execution Transcript I get this:

[15-04-13 14:22:39:887 EDT] FormApp.getActiveForm() [0.245 seconds]
[15-04-13 14:22:40:023 EDT] FormApp.getActiveForm() [0.083 seconds]
[15-04-13 14:22:40:057 EDT] Starting execution
[15-04-13 14:22:40:489 EDT] FormApp.getActiveForm() [0.425 seconds]
[15-04-13 14:22:40:726 EDT] PropertiesService.getDocumentProperties() [0.236 seconds]
[15-04-13 14:22:40:742 EDT] (class).getProperty([respondentEmailItemId]) [0.013 seconds]
[15-04-13 14:22:40:804 EDT] Form.getItemById([1914529909]) [0.061 seconds]
[15-04-13 14:22:40:807 EDT] Execution failed: TypeError: Cannot find function getResponseForItem in object [object Object]. (line 274, file "Code") [0.742 seconds total runtime]

I checked the line in the "Code" file and can see this:

}

/**
 * Sends out respondent notificiation emails.
 *
 * @param {FormResponse} response FormResponse object of the event
 *      that triggered this notification
 */
function sendRespondentNotification(response) {
  var form = FormApp.getActiveForm();
  var settings = PropertiesService.getDocumentProperties();
  var emailId = settings.getProperty('respondentEmailItemId');
  var emailItem = form.getItemById(parseInt(emailId));
  var respondentEmail = response.getResponseForItem(emailItem)
      .getResponse();
  if (respondentEmail) {
    var template =
        HtmlService.createTemplateFromFile('RespondentNotification');
    template.paragraphs = settings.getProperty('responseText').split('\n');
    template.notice = NOTICE;
    var message = template.evaluate();
    MailApp.sendEmail(respondentEmail,
        settings.getProperty('responseSubject'),
        message.getContent(), {
          name: form.getTitle(),
            htmlBody: message.getContent()
        });
  }
}

The code that says var respondentEmail = response.getResponseForItem(emailItem) is line 274

Any help would be greatly appreciated, I am a novice at this and am trying to learn some tricks. Thank you!