The Polymarket resolution for June 19th and 20th didn't get triggered by a later event on June 21st; it simply reflected that no military action occurred during the specified timeframe.
Prediction markets operate on a clear deadline, delivering an upper bound of certainty when an event either happens or doesn't.
Saying a strike on June 21st made the June 19th market resolve 'No' is like saying a typhoon in Tokyo on Sunday caused it not to rain on Friday—it’s an asymmetry in cause and effect that simply isn’t how these systems achieve their full expression.
The 'No outcome' was the peak certainty available once the clock ran out for those dates, independent of future events.