Did Miriel see what was coming?

[The Squatter of Amon Rûdh]

I don't think that we can say this with any great certainty. If she did forsee it, then her action was appallingly selfish, since Tolkien wrote:

In the Elvish legends there is record of a strange case of an Elf (Míriel mother of Fëanor) that tried to die, which had disastrous results, leading to the 'Fall' of the High Elves.
(Letter #212)

And in The Shibboleth of Fëanor he says:

While [Míriel] lived, she did much with gentle counsel to soften and restrain [Fëanor]. Her death was a lasting grief to Fëanor, and both directly and by its further consequences a main cause of his later disastrous influence on the history of the Ñoldor

Clearly if Míriel could forsee the Kinslaying and the Fall of the Noldor, then she could also forsee the part that her refusal to be rebodied would play in those events. She may have ignored the misery of her husband and son in her desire for peace, but could she disregard the well-being of her entire people? I think this unlikely.