It is plainly obvious by looking at them that they are duplicates. The CNRacing rep said they are duplicates. Nobody had the foresight to record the conversation, so I guess the people involved are liars. But then again, even if the conversation was recorded, the CNRacing guy could be lying just for the hell of it.
Even if I obtained a set of AMS manifolds and scanned them for comparison purposes against the MS manifolds, I'm sure casting variations between the two DIFFERENT manufacturers might cause them to differ ever so slightly.
In short, there is nothing that can be done to prove that they're copies to people who don't want to believe it.