Actually, “scam” is the simplest possible explanation, especially when the man in question is Rossi, a convicted scammer.
I was not aware he was convicted as a scammer, but was convicted for breaking a law that was passed after he was already in business that made his product illegal ex-post facto.
I think that the involvement of Defkalion is really quite clever. They will no doubt be able to shrug off any customer complaints based on unexpected trouble in copying Rossi's design. This could well insulate them from many legal traps.
I am amused that at practically the same time that Defkalion claims "My scientists found a way to make it. They need three months", they have also released a multi-page specification which calls out "10mWh" for "Controls and safety/operational electronics".
We are to believe that Defkalion is as yet uncertain of exactly how to make the working mechanism, but they are certain that it will take "10mwh" to power the controls.