Unable to transfer file ownership away from deleted ldap user

Nextcloud version (eg, 12.0.2): 15.0.7
Operating system and version (eg, Ubuntu 17.04): 18.04
Apache or nginx version (eg, Apache 2.4.25): 2.4.29
PHP version (eg, 7.1): 7.2

The issue you are facing:
occ files:transfer-ownership fails for a user. The source user is an LDAP user that has been deleted from LDAP but the user is listed in “remnats” and the files are still there.

occ ldap:show-remnants list the user with Nextcloud name:
E4D4373C-DC55-40E5-85DF-718C96A09137

occ user:list does not list the user though.

The files folder exists on local disk:

$ sudo ls -l /var/www/nextcloud/data/E4D4373C-DC55-40E5-85DF-718C96A09137/files
total 6144
drwxr-xr-x 11 www-data www-data    4096 jun 20  2018  Customers
[more]

$ sudo du -hsc  /var/www/nextcloud/data/E4D4373C-DC55-40E5-85DF-718C96A09137/files
4,3G	/var/www/nextcloud/data/E4D4373C-DC55-40E5-85DF-718C96A09137/files

Despite this, the transfer ownership fails:

$ sudo -u www-data php /var/www/nextcloud/occ files:transfer-ownership -vvv \
    E4D4373C-DC55-40E5-85DF-718C96A09137 509FA19B-B1C3-4042-AA40-115C804C48B2
Unknown path provided: 

How can I transfer these files to a different user before I completely delete the old user?