Yeah, the main issue with the story is, that we're not able to try most obvious ways to fix her. I finished the game for the second time few weeks ago with latest patch and there are some new dialogues, like they are trying to convince us, that she has to die, but the main issue is still present. We cannot use enriched infernal ore even common infernal ore helped us twice. Why???? Same with Gondians, there are dialogues about how they have newer heart models and so on, but can we ask them? No, why???? Have Karlach in party, talking with Gondians and doesn't have an option to ask if they can help is really stupid. Same with Dammon and enriched infernal ore in our inventory. If this is some side quest, ok, but this is main quest for your companion and even a origin character. Game with so many possibilities, where you can do almost everything, but not such an important choices??
As all avernus ending updates are far better than when I finished the game without any patch for the first time, the questions why is her quest so poorly designed still persist.