Restore backup after Update failed

Hi together,

After running the update, I only see “Update in process.” now.
The backup was abviously done, the folder in “updater-xyz/backups” seems to be complete.
The file structure in the root seems to miss some folders and files.
All status, remote, public and index.php are of the same size and only contain:

<?php
http_response_code(503);
die('Update in process.');

Since I’m running NC on shared hosting, I do have access to shell, but can’t use “Sudo”.
Can I just copy all files back from the backup to the root or will this approach fail?

Thanks and regards
Jens