And how often did the WHO insist that their stance, in any of these three cases which you didn't name, was correct after it turned out to be not the case?
Neither did they continue with these claims. Stop moving the gioal post. If we keep applying unreasonable near-perfect standards to one side and way more lax standards for the other we don't do good to neither side.
You're the one moving the goal posts. If a reputable organization thinks their statement was incorrect, they admit to it and issue a correction. WHO did not do that.