DLNA listens on WAN interface

[TheDreadPirate]

DLNA broadcasts would not go beyond the first couple hops. 4 is the default TTL. I wouldn't be surprised if your ISP's gateway would drop those broadcasts.

As for any concerns about DLNA listening on the WAN interface, you setup is atypical so I'm not entirely sure how that would behave.

If this were my setup, and I still needed Jellyfin accessible on the Internet, I would bind Jellyfin to the LAN IP and have my reverse proxy handle all external connections. This would mitigate issues with DLNA on the WAN port and still allow Jellyfin to be accessible without a VPN.