It’s been awhile since the moment of the question, but maybe a solution will help someone in the future.
Just define IS_WP_CLI variable in the beginning of your script .
...
define('IS_WP_CLI', true); // Avoid maintenance mode
require_once HOME_PATH . '/wp-load.php';
...
If IS_WP_CLI defined -> maintenance mode will not be instantiated.
if (defined('IS_WP_CLI')) { return ; }
Now you can run cli scripts even if maintenance mode is active.