It is generally not good writing to dangle a bunch of solutions to a problem in front of the reader, then skip ahead a bit and pretend there were no solutions without ever justifying why those potential solutions dangled previously were in fact impossible. It feels so horrendously railroaded and conveys a feeling of a desperate writer rather than a desperate character.
It's the same with V's problem in Cyberpunk 77. The friendly doc can't fix it and the corporation that owns the tech obviously isn't going to try, therefore V has no options and cannot be saved. Well, except there's a whole heap of other tech companies out there, all of whom would kill to get that tech. It's a nanite based tech so one presumes that enough EMP would slow them down a lot. They're following a programming, but why can't that programming be changed? It just cannot, because then the plot falls apart, therefore it is impossible!
Similarly, we have a character with a failing mechanical heart. We have access to a bunch of operational mechanical hearts of a newer generation. We have access to resurrection magic. We have a literal god of death on hand. Why is this even a particularly hard problem to fix, in the grand scheme of things? Why does it have to be? To be brutally honest, the ending here is fanfic level terrible. If it has to end badly then that's how it is, but at least make the story work. Make it meaningful. Make it an impactful statement of some kind. At least put in that much effort.
