Psst, where was it verified?
I think the 'verification' is when the water flow is checked by crude methods, the device emits some saturated steam for a while, then they do some backof the envelope calculations assuming that the water flow didn't vary for hours, and plugging in the values for superheated steam. In reality, as soon as there are bubbles in the line, flow goes way way down, and wet steam comes out. Just like you'd expect from a device drawing 400 watts. (assuming the second heating element, the one to cool and stop the reaction in an emergency

isn't also on...)
No attempt to put the device in a calorimeter. No attempt to make an accurate and continuous measurment of inflow. No attempt to make an accurate measurement of steam quality, no attempt to condense the steam and measure actual quantity of water evaporated. Just a 'hey look, water flows into the pitcher' followed by 'hey look it makes steam'. So does the hot-pot I use in my office to make tea. It draws about 400 watts, by the way. If I had some nickel powder in it, it'd still boil water.
This stuff is grade school physical science, maybe grade 7 or 8. Unless things have severely deteriorated, by that point a student should be familiar with calorimetry, steam, heating elements, all sorts of fun stuff. I'd expect an actual 'scientist' to at least adhere to a standard of practice that a grade school science class can manage.
As another random aside, I notice that the 'byproduct' of the 'nuclear reaction' is copper. There's probably no better material than copper if you plan to hide something in a nickel alloy. Pure nickel looks like pure nickel. 95% copper with five percent nickel looks like pure nickel. Nickel has very high coloring power in alloys and will overpower any of the colored metals. The 'nickel' coin in your pocket, at least for USA currency, is mostly copper. It still looks like nickel though. It won't assay as nickel. If I say 'here's some pure, specially treated magic nano-nickel, see as I put it in the reactor' it could have an awfully high percentage of copper and still look like pure nickel. Then you pull it out at the end of the 'reaction', send it off to the metallurgist, and pretend surprise at the copper content. I haven't seen anywhere where Rossi has offered samples of the catalyst BEFORE the reaction.