If I am guessing right, then this monumental decision will be to decide whether to keep her life support on, and eventually she wakes up, or turn off life support at some point and let her go? The letting her go, will probably be the end of the MC in terms of him doing things alone which would obviously be the wrong choice. Maybe I am entirely wrong, but I worry for Anna because the longer she is under, the higher chance she could end up with some kind of brain damage. Some thoughts about a coma is that the brain is trying to rewire itself for some reason or other, and the longer it takes the more neurons die and ive even heard brain tissue can die too if the coma is a long time.
I hope she doesn't have amnesia when she wakes up that would be a really cruel nasty mess for her to be in and the for the players too, please don't do that, even if it is the further the story, we already care about these fledgling characters.