Hi @jong
Have you also added the IPs of your computer and pgAdmin to the inbound rules? I'm asking, since it seems rare to add your home IP, usually a VPN or SSH tunnel is used instead.
I'm guessing these are the addresses you've added: IP to whitelist for Metabase Cloud instances
What do you mean about "no dice" - do you get a timeout after 5 seconds, or another type of error? Check Admin > Troubleshooting > Logs.