Confirming the following:
Host: Mac (Catalina 10.15) ethernet port 1802 set, running ethernet and wireless concurrently.
Mac user 1 (on host network) - could connect to the cloud campaign, can connect to the LAN campaign. (note, wifi must be running as this client doesn't have ethernet)
Mac user 2 (on remote OOL network) - could connect to the cloud campaign, can connect to the LAN campaign.
PC user 1 (shares network with Mac user 2) - could NOT connect to the cloud campaign, CAN connect to the LAN campaign.
PC user 2 (on Comcast network) - could NOT connect to the cloud campaign, CAN connect to the LAN campaign.
Steps to reproduce:
1. SET Port 1802 on your ETHERNET IP. If you need to, get iStats Menu to determine which IP is your ethernet IP.
2. Turn OFF wifi.
3. Launch Fantasy Grounds.
4. UPDATE
5. LOAD the desired campaign making sure Fantasy Grounds is using your ETHERNET IP
6. Turn wifi back on.
This should make your campaign reachable via the LAN protocol for both OS clients.
When I have time with the team, we'll test other conditions, but for now we are good to run the one-shot.