The GameStop saga was a David-versus-Goliath story pitting small traders against big hedge funds and a cautionary tale about what happens when fast-moving Silicon Valley collides with the heavily regulated world of Wall Street.Among its ensemble cast is one of the finance world’s most influential — and perhaps least visible — figures, the Chicago billionaire Kenneth C. Griffin.And when the House Financial Services Committee meets on Thursday to question key players in the GameStop madness, Mr. Griffin will be asked about the two distinct roles his companies played in a two-week trading frenzy that created and destroyed billions of …
