How Do You Use The Add Method In Tygh::$App['notifications_Center']?

I want to add a notification to a vendor that they will see in their notification center in the vendor panel. This notification will be added when a specific function runs. I've read up a bit on the Event Notification documentation in the Developer's Guide, and I've been trying things out on my end but I can't seem to get it to work.

$notifier = Tygh::$app['notifications_center'];
$notifications_array = array (
'title' => 'test title',
'user_id' => $auth['user_id'],
'message' => 'message test',
'severity' => 'N',
'area' => 'A',
'section' => 'test section',
'action_url' => '?dispatch=vendor_communication.threads',
'recipient_search_method' => Tygh\Enum\RecipientSearchMethods::USER_ID,
'recipient_search_criteria' => $company_user_id,
'language_code' => CART_LANGUAGE,
);

$notifier->add($notifications_array);

Anyone know why my code isn't working?