comment_meta_query
$meta_query = array( 'relation' => 'OR', array( 'key' => 'comment__in', 'value' => '$comment_on_hold', 'compare' => '=', ), );
$meta_query = array( 'relation' => 'OR', array( 'key' => 'comment__in', 'value' => '$comment_on_hold', 'compare' => '=', ), );