Yes, it does work with two servers as I have two servers running on my home network…
As for the port forwarding, you need different internet facing ports for each server… Personally I have external port 32410 forwarded to port 32400 of one server and external port 32420 forwarded to port 32400 of the second server…
As for trying to claim the new server, I believe I shutdown the first server while I tried to sign onto the second server from that system’s console using the localhost address an not the plex.tv one…