OK, the networking class was a few years ago, but I still use it quite a
bit...

Isn't part of the problem that the address you're trying to use on the
remote site isn't seen as outside the remote site's network segment? The
address you're trying to connect to is in the 192.168 range. Those are
internal, non-routable addresses. That is, that's the address that's
seen on the LAN side of your home router. What you need to connect to is
to the IP of the WAN side of your router, which will be some standard,
routable Internet IP address. If you're not sure what it is, you can try
Shields Up at www.grc.com, which will dig it out for you. Also worth
testing your integrity there, so you know if you're "showing" too many
open ports on the WAN side of your router.

Anyway, the IP address shown there is the IP address that shows on the
Internet, which is where you're going to get to your home system. The
way you're configured now, it's looking for a machine at the local
address 192.168.1.3 and telling you it doesn't exist (which would happen
if your local router at the remote site was dispensing addresses in,
say, the 10.0.0.0 segment, which is also not routable, but not in the
same network segment as the address you're requesting).

Now, the NEXT step, which is how to tell your home router, when you've
properly reached it, which private address behind it you want is one
step I haven't tried yet, so I'll leave that to someone who uses VPNs
more. May use the answer, if someone has it, myself.