Perhaps once Eric Cantor got wind of it the Obama team's plan to hide it or keep it for current or future blackmail fell apart, given that Cantor would immediately connect blackmail to Petraeus' early support of the false spontaneous video mob narrative.
Also at the time Petraeus was forced out, mistress Broadwell had already stated on Oct. 26 that Petraeus fully well knew it was a terrorist attack and knew that Delta Force had been requested...which you don't do for any irrate mob...and she intimated that Petraeus was frustrated that he had to support the mob story.
I have one question for the WaPo............Why did the President let 4 Americans get murdered on Sept 11,2012?