WordPress redirect URL by parse_request

add_filter('parse_request', function (&$wp){
    $qry = $wp->matched_query;
    if  ( preg_match('/slug=(.+)/',$qry,$matches) ){ //Change it into your pattern
        $slug = $matches[1];
        $postID = getPostIDBySlug($slug); //Check another Blog post in blog.simplylouis.com
        if ($postID != null ){
            $wp->query_vars['p'] = $postID;
        }
    }
});