Its worth pointing out that there is a wealth of evidence to examine. The seat itself will reveal what parts have been activated. The aircraft and in particular the canopy and the position of various items of kit will give a fuller understanding of what happened i.e did the MDC fire or did the seat punch through the canopy .
I dont recall any instances of seats being fired off on their own in aircraft so the important thing to find out is what was different to any other crew in.