bbPress.org

I finally found what was causing the problem after going through my functions.php.
Apparantly it was this function that was causing my bbp_topic functions to not function:

function SearchFilter($query) {
    if ($query->is_search) {
      $query->set('post_type', 'post');
    }
    return $query;
  }
  add_filter('pre_get_posts','SearchFilter');

After commenting this out everything seems to work perfectly fine now with all topic functions working and displaying correctly now.
I still don’t know exactly what it is but I probably am not using the $query stuff properly in here. Anyway the problem got much more clear now at least and can be dealt with much better now.