I think I may have figured out who the 'Twin' is:

Gavin Andresen
Chief Scientist of Bitcoin Foundation
iXcoin is an experiment to see what happens when mining subsidy is removed.
Here is your evidence:
https://bitcoinfoundation.org/blog/?p=204I gave Gavin a 5K IXC, along with other prominent Bitcoin community members at the time of Ixcoin launch. I think he sold them, but he did accept them.