Any possible way to make $wpdb->get_results() return anything else than array?

$wpdb->get_results() only returns arrays( associative or numeric) or an object. It does not return a string value.

If you want a string value, you need to use $wpdb->get_var() instead

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