I think the world should know that Pakistan is providing support to the Taliban so we know what kind of ally Pakistan supposedly is. Covering it up is just trying to appease the country and not spoil relations. Should the part about the heat-seeking missiles have been disclosed, probably not. If they would have withheld that part, they could have claimed they weren't harming the troops and it would have helped their credibility.
I actually think this will have little effect on the war anyways both policy and military-wise, and is probably more a media and political problem than anything else.