Hi Will,
I'm not familiar with the Cisco servers but it does look as if they have no physical connectivity. I would suggest first checking that the uplink switch ports are configured appropriately. As you said they show as being up and enabled, but do you get a link light on them at the host end?
Another suggestion would be to try this driver: VMware vSphere 5: Private Cloud Computing, Server and Data Center Virtualization
Lastly, I notice that those models also have two 10GB SFP+ ports...might be worth checking whether there is an option to disable them, if these servers have been used before there may be some old configuration causing issues...
Anyway, I hope I've been of some help!
Cheers,
Ben Loveday