NewId is good for this as it acts per row:

    $sql = $wpdb->prepare("UPDATE {$wpdb->base_prefix}my_table_name SET
                DisplayOrder = abs(checksum(NewId()) % 10000)
            WHERE ListCategoryId = %d
            ", $ListCategoryId);
    if (current_user_can('administrator'))
      $wpdb->show_errors();
    $wpdb->query($sql);
    
    //abs(checksum(NewId()) % 10000)      <<<Generates a random number between 0 and 9999