[Excuse you, that ass was one of his best friends. Rude.]

Even if they repaired the damage, there's no guarantee that he'd be a functional human being again. He might keep the same personality and behavioral patterns he had after the AI were gone, and that's the last thing we need.

[Remove Sigma, and he still acts like Sigma is running the show. There's nothing left of Maine; what's the point of trying to keep a monstrous shadow alive?]

Honestly, if you can do it quickly, that might be a mercy. I'm pretty sure his last death was slow.