So what are they going to do? See if engines didn't break and plane hasn't crashed - and based on that declare flying safe? Where is the logic? A single successful flight does not say absolutely anything about general safety of flying in these conditions.
World aviation agencies spend countless hours certifying aircraft for simpler and better understood conditions such as flying above water or in winter etc, and only then give a "go" based on significant test data when appropriate measures are worked out. And here they want to let planes fly into known hazard based on 1 hour of flight time without any additional specialized equipment, knowledge or testing? I know they want to make money - but surely a single all-engine flameout event would cause them more issues and will ground them for even longer. Very very shortsighted.