ELAC -
Without knowing what route they took through the area and where they were relative to what they could see of the weather (visually and/or on the radar) we don't know enough to draw any conclusions as to the wisdom of their choices.
Fair enough. However, other flights apparently got through that area, not only that night but other nights as well, without problems. As we keep saying, we'll know when we know and even then, we probably won't !!