|No. You can be sincere in your initial efforts, then, when challenged, want to avoid explaining yourself.|
Won't wash. The explanation they gave - "we got bad intelligence" IS the alleged coverup.
Logically, either they were sincere and thus there is no cover up (unless you want to discuss the CIA's attempts to cover up and distract attention from its dismal track record), or they were insincere and "intentionally misled" the nation into war, which is the charge being made against them.
You can't have it both ways. Greeley is trying to.