No, you're missing the point. You don't need to add anything to the routers or have any control over your work network at all. You merely need to add an entry on your local work PC.

Here's how it works.

Let's say your home network is 192.168.0.xxx with a subnet mask of 255.255.255.0.
Let's say your work network is 10.134.75.xxx with a subnet mask of 255.255.255.0.

You set the player address to be fixed 192.168.0.42 with a subnet mask of 255.255.255.0. It works on your home network.

On your work PC, you go Start/Settings/Control Panel/Network.

It's already got one TCP/IP protocol entry that's set to 10.134.75.yyy with a subnet mask of 255.255.255.0.

You merely need to add another TCP/IP protocol entry that's set to 192.168.0.zzz with a subnet mask of 255.255.255.0. Right there on your PC. Then your PC will correctly talk to the player.

See? The trick is understanding that a subnet is merely an arbitrary address mask and that your PC can talk on any subnets you tell it to, even multiple ones.

You could also do this the other way around if need be. Once you understand the concept, it's really easy.