My impression is that Arrington realized how bad Fusion Garage was and why there was discussion of a new company being formed. He probably just thought they could get the product out and then deal with the issues, not realizing the backstabbing by Chandresekar was already in motion.
I have an opposite impression. It could be that Arrington, seeing the business relationship went bust and that he made little to no contribution to the device and thus has little to no rights on it, decided to attempt to get FG's work for free, by suing them out of business and forcing a settlement on his terms.
I expect him to be able to prove that FG has and continues to engage in shady deals.
Actually, I hope not. I would love to see him fight off a slander lawsuit.