I still think we are being a little unfair on the FE here. His job is to monitor the engines' health, he sees 1,3 & 4 working properly, he hears on the radio that they have a fire in the vicinity of the No 2 engine and notices a reading on his instruments that tell him No 2 isn't that healthy. The two guys facing forward seem to have rather a lot on their plate and why should he add to their burden?
Never-the-less from reading all of these posts it seems that breaking more than one link in this chain would have been needed for this tragic event not to have occured.