From the Report

One would hope to believe you were safe above the published MSA.

It appears you cannot rely on the published MSA.

That’s a very valid point ! Wombat. Sort of makes the the other causes superficial.

I don't know about the type in question, or at the accident location, but on other types I have flown in mountainous territory EGPWS got triggered even when accurately flying a published approach due to terrain ahead before intercepting the loc, or else terrain directly ahead on the go-around. I remember this being the case at Berne, Sion and Chambery. Where we knew that EGPWS would be triggered we (after a careful briefing) also pulled the CB because there being no cockpit door it could clearly be heard by pax.

I am not saying this is a recommended practise, but we considered the risk of having a panicking passenger bursting into the cockpit greater than the risk of a true alarm on approaches that we knew well and had flown recently.

Not necessarily, the 8300 is a true height while 8000 is an altitude based on whatever baro setting is used and influenced by temperature.
But then, it would need low temperatures and pressures that occur over Greenland, hardly the case here I suppose...

It looks to me from the VFR chart that the highest terrain within 25NM in that sector is over 14000ft which would mean the real MSA is over 15000ft, in other words the published MSA is completely spurious. Was the chart produced entirely by the operator?

The chart depicts an MSA within 20nm of the airport. The report does indicate that this is an entirely operator produced chart.
So yes a work of fiction bearing no relation to reality.

I have done quite a few landings in Sion with various aircrafts and certaiy don't remember such occurrences, although I can imagine a G/A triggering it.

What type if I may ask?

If your EGPWS triggers during a straight in ILS approach in Bern you may want to heed the warning...

atakacs

This was on various C525s and C510. Quite a few years ago now so memory not that precise. But I do remember a colleague had a panicking passenger run into cockpit on an approach into Bern, so we used to pull the CB on subsequent approaches. It was something we used to do only after careful briefing, and if it was a pax we did not know. If a regular pax, we would brief them that the alarm might be triggered.