NC 26 Update on hosted system: OCC command not possible

I use a hosted NC with a data directory outside the nextcloud root directory.

Before NC 26 (since about NC20) I could run the OCC command (via SSH) for missing-indices by activating a temporary config.php, pointing to this outside datadirectory:

<?php $CONFIG =['datadirectory' => realpath(__dir__ . '/../NC'),]; ?>

Now this does not work anymore an rises an InvalidArgumentException:
“No data directory set in PATH_TO_NC/lib/private/Files/Storage/Local.php:77”.

Has anyone a hint to solve this for NC26?

Best regards,