WSOD "The provided host name is not valid for this server"
You need to add your domains into the array as per your first example. I.e.

    $settings['trusted_host_patterns'] = array(
  '^www\.yourdomain\.co\.uk$',
  '^yourdomain\.co\.uk$',
);


Then clear the caches and the message should go away. It may be that you're missing the comma after your second entry.