Deluge auth file in docker

In the container's Volume and Bind Mounts | Container path, you made a setting of /config and linked that to a Host path directory. The auth file is in that Host path directory.

I strongly suggest not running the way you are with no Container path set and therefore it not being linked to a storage location on your system that you can directly access while the container is stopped.

I use /home/fred/.config/deluge for my deluge docker's Container path /config location.

All the others are similarly located in /home/fred/.config/, ie:

/home/fred/.config/sonar
/home/fred/.config/jackett
/home/fred/.config/nzbget

etc.

Plex is the only exception as its /config is enormous and not suitable to place where /home is located.

You can set it the way I suggest, and once the container is started it will be created there. You can ssh in to the box, navigate to that location , and then list the files to see what's there. You should probably install a copy of Midnight Commander for things like this.