Originally Posted by
gem1
This may provide a clue as to what broke first.
No it won't. Because it seems most likely that the TCAS was reporting a fault due to erroneous airspeed or altitude data - just like half the systems on the aircraft at that point. (Exaggeration, but you get the idea)
It's already been pointed out that 23 of 24 (at least) ACARS messages share a potential common cause in air data sources. It would be dangerous to assume an independent cause for one of those messages at this point.