My employer was fined in 2013 for having an unlicensed vCenter server. Fortunately I was not involved with that!

The fine was in the 10s of thousands of dollars. And now I want to build a lab....at work. How do I do this without getting into trouble? Is my employer accountable for vmware software I download & use in the work lab from a personal email account on a trial basis?
Let me be clear - my employer is perfectly fine with me labbing at work. I can even connect from home via VPN to a work lab whenever I want. I'd rather they pay the power bill, and I'm also being provided with some fairly decent hardware. I'm being actively encouraged to become an expert in vmware.
My lab consists of two repurposed workstations:
- unknown HP - 12gb ram, 4 250GB SATA drives, debian x64 that can run vmware player/workstation. The USB ports on this box are bad, everything else works just fine.
- HP z800 - 48gb ram, 2 8 core intel xeons, 4 250GB SATA drives. Has Windows 7 right now, but I could p2v the OS and run it as a VM on top of ESXi. Should I run vmware player/workstation on this computer or install ESXi?
- 1 2TB USB3 hard drive, 1 500GB USB2 external HD....no usb 3 ports that I can use, though
I want to be able to play with DRS, HA, vMotion, and hopefully have some sort of VSA to hook into the virtual environment. I've got 2 work provided laptops that I can use to run the vSphere client from.
How would you recommend configuring all of this to fully cover the VCP5-DCV exam blueprint without embarrassing myself by getting my employer fined? If it matters I'd like to test on the 5.5 exam blueprint.