The first link is to one of the more bizarre engine stories on the internet. There appears to be something then it turns into another paranoid inventor who took some details to his grave that make duplication very difficult. I used to write these all off now I am searching for some kernel of truth to make sense of it. More below.
When I was a kid I had a 2-stroke motor cycle engine run quite normally with the ignition cut off. I also read the stories of Russ Bourke. He achieved remarkable specific fuel consumption numbers with 2-stroke engines with restricted exhaust ports in the 1950's and earlier. He was widely discredited as he had no formal engineering training. He made some mis-interpretations and describe some things somewhat peculiarly. Never the less Honda developed an Active Radical Combustion system proving that there was another way to burn fuel in an engine. This had been Russ Bourke's main contention. Today many labs are working to optimize and control HCCI.
These so called plasma engines and Joe's cell or whatever are no better understood or accepted today than HCCI was when I was a kid 45 years ago. I may not live long enough to understand them but I am claiming that there is some kernel of truth in these anomalous stories that might be used for cheaper prime movers.