Ah, I blatantly overread the word “remote” 😉
Well, Rendezvous proxy is pretty much the only thing I know of that works with remote firefly’s.
You could achieve the same thing when using ssh, or openvpn to connect to the remote lib and using avahi, IMHO.
IIRC someone has achieved this and posted about this here on the forums. (If it wasn’t even Ron himself)