Conso
To assume that ACARS must have transmitted loss of cabin pressure in a compromised situation is unwise. It is also unwise to assume that a bomb would immediately destroy all systems or for that matter properly explode or rupture the cabin.
These ACARS transmissions may only be a small subset of fault conditions prior to being completely disabled. However, the idea of a fire taking hold and disabling all communication and a number of other systems in 2 minutes, or so, is unrealistic.