Nextcloud join script fails on a fresh install of ucs 5

i created host entries, so usc-sso resolves and more.
by coincidence a nextcloud app update arrived, which i could upgrade to.
Also rerun all join scripts with “force” flag.
Still nextcloud join script fails with:

There are no commands defined in the “saml:config” namespace.

Could not create LDAP Config at Nextcloud
EXITCODE=1

Nextcloud does not integrate into LDAP due to this, so no ucs users.

What am I doing wrong here?
@tanatos ?