Yup exactly the same outcome as you guys but still fail to join. Typically when the server is up and running, there should be output in the log located 7DaysToDie_Data/output_log.txt. Where it generate the world and if you try to join during that process you will get a "Server is currently initializing, please try in a few minutes".
Just wanted say THANK YOU! I spent so many hours on this and i am only implementing only on internal ip only...LOL
Set Unraid http/https port from 80 and 443 to like 180 and 1443 ( Unraid Settings - Management Settings )
Set Nginx-Proxy-Manager-Official docker setting to listen to 80:80 and 443:443
If you are using Adguard, then set DNS rewrite like plex.local to YOUR UNRAID/NGINX IP (192.168.10.100)
Configure NGINX proxy to point plex.local to 192.168.10.100 and port 32400