Hi,
I have limited experience with the CX but what I think you can do is "evacuate" ESX1, ie. move all VMs on ESX1 to ESX2. Remove it from storage group "Test.Dev" and add it to "Production".
Just a reminder, the EMC CX3 is not supported with vSphere 5.x, latest supported is 4.1U3.
Regards,
Martin