How can they call it editing when the narrator specifically states that Klingon intelligence has learned that the ships are being built there? Unless they were feeding them false intelligence it seems pretty clear. If they were feeding them false intelligence, then Kharn isn't as good as they say he was because that would be something that you would want confirmed by actual eyes on sight, be it by long range probe or a person seeing it, before committing a bulk of your forces for an invasion.
As far as STIII, you may be right. I read that a looooong time ago some details may have been lost.