The version I saw is that they were games he made himself (not sure if it was his own design or print and play). Either is an abuse of power but playing his prototypes would be particularly egregious.
The article does say they were self-made, but I don’t know if that necessarily means they were of his design, or just existing games that he cobbled together in order to play them. I would suspect the former, but it is unclear.
Friends! Friends! This is terrible! This is where amazing new designers come from (Japanese fire stations, if I’ve done my calculations correctly)
The Japanese version of the same report is clearer that the games were like card games played with a regular deck and a word game where the next player has to say a word starting with the character that the previous word ended with.
That doesn’t mesh well with the description of self-made components, but it does imply the games were very simple designs.
I like the juxtaposition of “coerced” with “ignored people who refused to play”. Exactly how I picture soft “coercion” working here, and the pressure people felt to play and probably had difficulty refusing.