Firstable I would like to propose my help for this work, ask me what you need, or I could even do it for you if you give me the configuration file.
In nethserver you have an helper try
account-provider-test dump
It will print all you need for an authentication, if the bind is local or remote, samba AD or OPENLDAP.
This is an example in perl how to authenticate user in dokuwiki, no matter it is samba or ldap, we detect and write the template accordingly
The idea is to do the same in the volume of docker, I assume it is possible in /var/lib/docker/volumes/docker_piler_etc/*
we could create a template to write the configuration and restart the container once it is done (or restart only piler if it is possible)