I dont have an MD3200 so I have no idea what you are talking about.
I was referring to this:
I was hoping to integrate this with our existing MD3000i or MD1000 but apparently it is not possible.
MD3000i or MD3200i same difference. I don't understand where you jump to the conclusion "not possible". Not only is it POSSIBLE, but there is a step by step included in the manual. Did you try calling Dell? They can help with BOTH ESX and the MD3000i at the same time, and help you set it up. But they will tell you the same thing, it's in the manual.
Also veeam will work for ANY target you setup, provided you configured the MD3000i properly and ESX. Some features won't work in a VM, so veeam MAY require a physical machine to properly be setup.