Although, the device that sits at your work, doesnt it allow traffic on 4899?
So if you tunnel into work, aren't you sitting "at work?" So... you can remote into all the work PCs as if you were on their LAN?
When I tunnel in (we're using CheckPoint) I, of course, get a local IP address within my office's LAN. Radmin works perfectly by IP. It doesn't work well via DNS since we have our own internal DNS servers.
You can use SSH's port forwarding function to do what you've asked. You'll need an SSH server at home, and an SSH client at work. Check out OpenSSH for Windows for your server, and putty or Entunnel for your client.
In case you're not as network savvy as some of these folks, I'll simplify their explanations:
Basically, to RAdmin to your work computer from your home computer, some sort of hole thru your company's router/firewall needs to exist. Whether that hole is a port forwarded to your machine (or another machine, so you could connect to yours using connect through host), or a VPN, or something more esoteric like the SSH suggestion mentioned, depends on your company network, its existing set up, and how much control you have to make changes in the config.
Oh, wow, I just looked at the dates on these posts. I suppose you've either fixed this or given up by now. Well, if not, post again and we the people will continue to try to help.