What was foreshadowed by Madame Schacter’s nightmare?

night

Madame Schachter's nightmare foreshadowed the annihilation of many of Elie's Jewish family and neighbors in the crematoriums at Auschwitz-Birkenau, the largest of the Nazi concentration camps during World War two. ... Schachter's nightmare foreshadowed death and the loss of humanity.

The train being set on fire was the foreshadow.

- "the die is cast; i have consented to return if we are not destroyed. thus are my hopes blasted by cowardice and indecision; i come back ignorant and disappointed. it requires more philosophy than i possess to bear this injustice with patience. i have lost my hopes of utility and glory; i have lost my friend."