Decent concept [@SimplyJohn], except for one thing... The Grand Master at the time of the Sacking, Zym, wasn't on Coruscant at the time. He was on Alderaan, negotiating the peace treaty with the Sith Empire.

Also, why would the Grand Master be summoning him anyways? There were tens of thousands of Jedi, if not hundreds of thousands. Thus knighthood isn't something truly special for the leaders of the order to get involved in. They had more than enough to do with the war effort and the peace negotiations.