Right on, PJ2.
One detail though (and this also addresses PBL's quandary): there is out there a reasonably-sized data set for ACARS messages sent during A330 pitot-tube icing events. Air Caraibes had a couple of cases (although from the report pasted, the principal diagnostic detail was the early rudder travel limiter fault). Air France had something like 6, and they obviously have the ACARS messaging practices that interest us. Presumably, other carriers should have something analogous.
So, while everyone's running around crowing about a cause, I'd suggest that, if that is the cause, someone has a body of information with a good shot at confirming or falsifying the hypothesis pretty quick. While it helps to do the piece-by-piece analysis, it helps even more to associate the whole list of messages with similar cases where the cause is known.
...not that we have access to that sort of information, mind you, but someone who did might find it illuminating.