I checked the code but it seems a hook is still missing in the place you want.
However, I can give you a temporary fix, which will be removed on update on Vibe course module plugin but you can follow below steps again to get the job done.
- Go to WP admin - plugins - editor - vibe course module - includes - bp-course-notifications.php
locate the function "instructor_emails"
And just before the last statement return $to; , you can add your email in the $to like :
$to[]='[email protected]'; just before the return $to;
so it appears like this :
$to[]='[email protected]';
return $to;