You know, in a way, Stratt wasn't just Earth's scapegoat... she was also Grace's.
She knew he would rise to the occasion because he'd done it before. He had to be coerced into working with her in the first place, but he bravely chose to come back after being told he could leave after being a whole ass bitch about being wrong and having a fairly valid crash out. It was, at the end of the day, his insistence that he continue and to be given a few dots. But in doing so, in coming back, in staying to see it through, no matter what happened he had made his bargain with fate.
There's a high chance that Grace would have faced prison the same as Stratt. He might have been the leading scientist on astrophage, but he was also, by all accounts but his own, her right hand man.
In the tragedy of both of their stories she sacrificed him. There's no denying that. But in doing so she spared him a life she must have known was coming after the dust settled.
This anxious, apparently socially oblivious genius dumbass guy that everyone likes, had to be elevated after he made a discovery too big to ignore, on his insistence to be given a chance to do so.
Was it selfish of her to share the weight of the world? To bring him everywhere, to have him tested for the coma gene same as herself? Maybe. But she was doing some serious emotional labor for the entire world.
So... He was already doomed. He was his own separate trolley problem that she took on the emotional labor to solve.
