How may Citadel have blindsided & forced OpenAI researcher to sell nearly all of what he owned?

Ex-OpenAI researcher Leopold Aschenbrenner's Situational Awareness sold the bulk of its public stock bets despite recording 439% gains. Notably, a Citadel executive hinted at a possible quarter-point rate hike days earlier, which panicked investors and reportedly caused an AI selloff. This then crashed Aschenbrenner's stock bets, forcing him to sell them to Citadel at significantly lower prices.