I'm with TC (an a few others whose names I've forgotten already) on this.
Let's be realistic. You will NOT stop people wondering what happened. And it's normal for them to share those speculations with fellow aviators. So they'll post them. Now, look back at other threads where this has happened. The original speculating would probably have been long forgotten. But what usually happens is that someone says the post shouldn't have been made, someone else argues for free speech, a third person wades in and demands that all speculation stop, the next one flames the previous poster for telling him what to do or not do, etc etc etc.
Suddenly one speculation becomes an all-out argument! And for what? Because the original post might be wrong? Because one person might have suggested a pilot made a mistake when he didn't?
We've had the pilot from a recent accident come on PPRuNe and explain what he thought happened. We've had relatives and friends come on and thank people for their condolences, and for caring enough to post at all. But as I recall, we haven't actually had anyone - except other PPRuNers - complain about people speculating in a perfectly human fashion as to what happened.
Live and let live might not be perfect, but it's better than any of the alternatives.
Cheers,
Whirly (with a "Y")