phpword in an EventSubscriber

Question

I want to download a Drupal page to a Word document in an Event Subscriber. The code I'm starting with will download a document which msword will open. Here's the original code:

protected function setResponseContentToWordDocument(ResponseEvent $event) {
  // Get response.
  $response = $event->getResponse();

  // Get response's HTML.
  $html = $this->getResponseHtml($response);

  // Update headers.
  $response->headers->set('Content-Length', strlen($html));
  $response->headers->set('Content-Type', 'application/msword');
  $response->headers->set('Content-Disposition', 'attachment; filename=' . MskString::filename('word_doc.doc'));

  // Set content to html.
  $response->setContent($html);
}

But the response html includes everything, which is too much. I would like to try the phpoffice/phpword library which I've used in the past in controllers.

The problem is the file is silently downloading to the /tmp directory, and not downloading in the browser. Here's the code:

  protected function setResponseContentToWordDocument(ResponseEvent $event) {
    global $base_url;

    $filename = 'my_file';

    // Create a new Word document.
    $php_word = new PhpWord();

    // Add styles.
   ...

   $section = $php_word->addSection();

   $node = \Drupal::routeMatch()->getParameter('node');
   $html = $node->body->value;

   Html::addHtml($section, $html, FALSE, FALSE);

   // Save the document as OOXML file.
   $writer = IOFactory::createWriter($php_word, 'Word2007');

   // Create a temporary file in the system.
   $temp_file = \Drupal::service('file_system')->getTempDirectory() . '/' . $filename . '.docx';

   // Write in the temporary filepath.
   $writer->save($temp_file);

   // Send the temporary file as response (as an attachment).
   $response = new BinaryFileResponse($temp_file);
   $response->setContentDisposition(
     ResponseHeaderBag::DISPOSITION_ATTACHMENT,
     $filename . '.docx'
   );
   $response->deleteFileAfterSend(TRUE);

   return $response;
}

The above code downloads my_file.docx to the /tmp directory. If change return $response; to $response->setContent($temp_file);, a LogicException: The content cannot be set on a BinaryFileResponse instance. error is thrown. How can I download the word file in the Event Subscriber like in the Controller?