Kilrah

"I simply VPN in and load the Octoprint server by IP to check the status..."
My point earlier is that a software/hardware VPN out-of-box usually shares NETBIOS broadcasts to make things easier for the remote user. If Samba is broadcasting the NETBIOS name of the printer once per minute then you might try connecting to it via my-c2.local (whatever your serial number is) to see if the name broadcasting makes it thru.