my posting has been deleted, which I find highly unfortunate.
Let me rephrase:
It's highly unlikely that anything broke exact at the same moment when they entered a CB. Much more likelier is that first they entered the cells and then something happened.
The error messages on Acars are therefore not the cause, but the outcome of the accident. You will not find any information about the reason by looking into the technical details.
I have never experienced heavy icing (or even light) outside of clouds in the tropics. And never severe turbulences.
So it's pretty likely that they first entered into a storm system, then they experienced all the problems.
We should therefore concentrate on arguing about why the crew should have entered a thunderstorm system.
Dani