These problems are not usually an instant spontaneous catastrophic event.  Most likely a chain of events that could have stopped and the incident prevented.  I find the report inadequate and hope authorities made a better attempt than assuming it was "something in the stove".
  Any burn requiring skin grafts is horrible, painful and permanent.
  I don't want to assume anything as the cause there is just no evidence here--but this would be a good reason NOT to use the stove as comfort heating.  You could fall asleep, flame goes out but continues passing gas until you hit the percentage required for combustion.  Not less and not more.

  Inspect your gas lines once in a while, use appliances as intended.

  Chirs C 90mv