Trying to use WP_Query to display a custom post type

Typically, you would be echoing content from an action hook, rather than returning it, and from I can find about this Woo Theme hook that looks to be the case here too.

Try echo $output; instead of return $output;

See:
Clarification on filters and hooks
Difference Between Filter and Action Hooks?

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)