I don't mind him being saved or coming back to life. What I do mind is him potentially not getting some sort of penalty for his fuck up, which Idriel's words seem to heavily imply. My read on her words is that she isn't just berating him for being arrogant, she is berating him for deviating from the path she had laid out and the setback might have consequences pertaining the success of Orion's quest to "break the chains." Him opening the letter doesn't fit with that narrative because that would imply that Orion never deviated, he is still on the damn path, thus making Idriel's words essentially hypocritical/contradictory.