Yes, the mullvad integration is essentially what I am trying to achieve because I cannot run both vpn and tailscale as they conflict. Unfortunately I need mullvad on other devices and have spare device slots I can use so it makes no sense to pay another $5 on top.

I was hoping that requests to the jellyfin port would get returned back through tailscale directly and anything else goes on to gluetun. The subnet option sounds like this would be the solution but I could be misunderstanding many things here.