...Trust me, I know Will and Dain very well. I complain to them constantly about their lack of transparency. It is hard though since it is a very sensitive topic. Will even did a GDC talk about how the Kickstarter didn't get them enough money to actually make the game after sending stuff out so they turned to making another game for cash, which completely flopped and basically destroyed their company. The game was Will's first game design but remade and having his "first baby" kill the company almost destroyed him. I found it on the GDC vault. You can watch it here:
http://www.gdcvault.com/play/1021972/Failure It is basically a metaphor of a fail relationship with the "bad girl" or something.
He was also juggling running the Philly Game Forge and a few other projects. Which he says in retrospect was a horrible idea to try to manage all those things and work on Duet at the same time. I'm sure they will finish the game eventually, and I know they do work on it from time to time, but who knows when it will be released which is the sad part.