> Is there remotely any reason to believe you could put their brain back together in a functioning way or that the connections are even still there cryopreserved like this
This is a well studied area, and there's good reason to believe the damage isn't unfixable/absolutely devastating to the brain structure. https://pubmed.ncbi.nlm.nih.gov/22533424/ is a paper specifically on this.
If we can recolor jpegs from the 1800s, I'm confident we'll be able to recover frozen connectomes.
I wouldn't place any limit on our future computational abilities or techniques. And even things that lie beyond the limit of detection may fit some into some clever model we've yet to imagine.
This is a well studied area, and there's good reason to believe the damage isn't unfixable/absolutely devastating to the brain structure. https://pubmed.ncbi.nlm.nih.gov/22533424/ is a paper specifically on this.