I thought I got the actual MAC (probably not) of the miner by doing the wireshark trick and whitelisted it, but apparently it's not the MAC here as I couldn't connect to any of the devices on the network via a browser. Anyway, I got a router in the mail - hopefully tomorrow should work!
Thanks again for your help!
I'd cancel that router .. but in the meantime, go here >>
http://www.dhcpserver.de/cms/Install that on your laptop. Take 1 cable and connect it between the miner AND YOUR LAPTOP.
You'll get a "mininetwork" with only two items on it. The miner will receive an IP address from that software.
Then you can browse to the miner address and find out the mac address to add it in your office configuration.
You can also set it to a fixed (known) IP address, add the office gateway information, then plug it in the office network.
You don't need the office DHCP server to give you anything. Just "take what you can, give nothing back" .. that's a saying from Pirates of Caribbean ..