Sooo, I was able to fix my own problem, but it wasn’t particularly easy...I’ll post the solution here in case anyone else experiences the same issue in the future.
After lots of troubleshooting, I was convinced my server config was ok. Though I had rebooted the router, I had not yet reset it to factory settings. That did the trick. Of course, then I had to completely re-do port forwarding. Also, I had a new LAN IP for the unRAID server, so I had to reconfigure many of my docker apps that used APIs to communicate with one another (Lidarr, Radarr, Sonarr, Deluge, Sab, Organizr, etc).
All good now, but it would have been nice to have that Friday evening back!