Order users by random not working?

Ok, so I found this solution in other thread which did worked:

Added this to functions.php:

add_action( "pre_user_query", function( $query ) {
    if( "rand" == $query->query_vars["orderby"] ) {
        $query->query_orderby = str_replace( "user_login", "RAND()", $query->query_orderby );
    }
});

It sorts users by a random order now!