Here's a miserable plot possibility. Hermione was concealed, something went wrong, and the feeling of her mind going past was because a number of other things happened, and the concealed Hermione was killed.

This seems unlikely. This would end up sounding a lot like "don't tamper with fate". That sort of thing is very common in time travel stories where someone tries to save someone's life, but it has a massively anti-transhumanist, pro-deathist vibe. I doubt Eliezer would do it.