Don’t use jellyfin.server.local

.local is reserved for mdns, which doesn’t support more than one dot. (Though it may still sometimes work).

In any case, to make that work you need either a DNS server on your network or something like duckdns (which supports wildcard entries).

makes software for pirates

please avoid pirated versions

Good luck with that.

You can point your frontend reverse proxy to the docker reverse proxy.