Extraordinary claims require extraordinary evidence. That goes both ways. At this point with so many people involved, it would be an extraordinary scam. All we can do is wait for more evidence... and speculate the effects of such a device...
If it does work... oddly enough, the short term big winners might be companies that the environmentalist hate the most. Mining and oil extraction require massive amounts of energy, if those energy cost were to drop, these companies would most likely be able to hold on to their margins. While the purchase cost of these products drops consumption would increase. Until battery cost decrease, people will still be driving (and factories producing) ICE vehicles. It is not totally inconceivable that cold fusion would "kill" the electric car... for a while.
I've see this written somewhere else, but shorting commodities and going long on refineries might be a good plan.