Sadly, a 30 year old Dutch climber has fallen 200m and been killed while descending the Lower Moseley slabs on the Hornligrat route last Saturday. It appears to have been a failure of the fixed anchor used for the abseil. I roped down off the left-most upright of the terrace handrail at that location last week. The other option I recall seeing there was a thick metal pig-tail thing that looked well secured to the rock below the terrace. I assume he was using one of these options, although there may well be other places to rig an abseil at that spot.

Article in French with further information http://www.lenouvelliste.ch/fr/valais/valais/un-alpiniste-hollandais-de-30-ans-a-perdu-la-vie-au-cervin-samedi-498-1213464

The SAS story (copied in your link above and several other news outlets) uses the phrases "piton d'amarrage" (tie-off piton, anchor piton) and "hamecon de forage" (drill hook), saying the rock it was in broke free. Sounds like a bolted anchor, not the handrail.