Port Forwarding and Ether5

I just received my hAP AC today and have mostly everything set up correctly. I think there is a simple answer for this but I did not see it in the documentation. Is there something different about Ether5 that would make devices plugged into it not show up under DHCP Server → Leases? I have my router at 192.168.1.1 and my DHCP range 192.168.1.101-254. With my previous router, I had set a static lease on 192.168.1.10 for my Raspberry Pi 3 running Pi-hole. With it plugged into Ether5, I cannot see it under Leases at all. I am sure there is something obvious I am overlooking.

Next, I am desperately trying to properly forward a port for Plex. I have my FreeNAS box at 192.168.1.2 (static lease) and Plex runs at 192.168.1.3 (set within FreeNAS) and port 28042. I can access the page but somehow it is unable to find its own server. Nothing configuration wise on Plex has changed. I have tried forwarding the ports and I believe I must be doing something incorrectly. I currently have:

Chain: dstnat
Protocol: (6) tcp
Dst. Port: 32400
In. Interface: ether1
Action: dst-nat
To Addresses: 192.168.1.3
To Ports: 28042

So it comes in from the outside as port 32400 and in the network should redirect to 28042 where the server can be reached. This is exactly how my ports were forwarded in my other router (at least in theory, I obviously entered something incorrectly in the hAP AC). I saw others entered their external IP but I did not think that was necessary. To rule out Firewall settings, I disabled all of them and continued attempting to reach Plex from outside of the network.

Any help will be greatly appreciated.

Okay, silly mistake on my behalf. The port forwarding is working now. However, I am still very curious what I am missing in regards to being unable to see a lease for what is plugged into Ether5 (Raspberry Pi running Pi-hole… set statically on last router and is keeping 192.168.1.10 address).