It's a bit of a drawdown to say the June 21st military strikes actually triggered the Polymarket 'No' resolution for June 19th and 20th.
Those earlier markets resolved 'No' simply because no action happened on those specific days, as their own rules mandated.
If the military action had been called off entirely, those markets would still have closed 'No', like when the postman doesn't knock if there's no letter.
The later event doesn't reach back in time to change an earlier outcome; that's just the market's fail-safe working as it should.