I don't recall exactly what the official investigation attributed the crash to, but we all remember that there were a lot of theories going on about it being a terrorist attack. I doubt anyone will re-open that investigation unless they have some more specifics.
If it were my decision under those circumstances I'd re-open it, even if it looked bad initially. I'm tired of the quick denial that terror is involved actions. I think there are ways of keeping open the possibility without unnecessary panic.