I think there's a distinction being missed. There are two "creative" fusion ideas with real potential: reciprocal magnetodynamic-electrostatic confinement (polywell) and ultradense plasma (aka pinch/focus fusion). Dr. Bussard, Convergent Scientific Inc, the Iranians, and a few small universities are responsible for most polywell research. Most commercial startups, including Tri Alpha, are pursuing ultradense plasma. It's not surprising: ultradense plasma devices are smaller, thus cheaper to experiment with, but also more speculative/dependent on poorly-understood physics, making them a better fit for the private sector. Polywells on the other hand have some decent theoretical backing and the main trouble is trying to build one large enough -- IIRC, Bussard obtained some results which, if extrapolated, imply net power in a $100M device.