How to change the title of breadcrumb?
You could use a title callback, like for example this one from the core node controller:

\Drupal\node\Controller\NodeViewController::title

  public function title(EntityInterface $node) {
    return $this-&gt;entityManager-&gt;getTranslationFromContext($node)-&gt;label();
  }


Your title callback would have other route parameters, so that you can find the correct node, see also https://drupal.stackexchange.com/a/248687/47547.

When using the default option in the Bootstrap theme to display the page title you might need to add cache metadata to the breadcrumb, see Breadcrumbs are cached, which depends on how you determine the node to display.