In what ways do you think the mythological figure of Cassandra and Madame Schachter in "Night" are similar?
You've asked for an opinion, so that's what I'll give you. The only similarities I can see between them is that they both had visions and they both were thought to be crazy.
Cassandra was the daughter of Priam and Hecuba of Troy. When their son Alexandros was born, Cassandra foresaw that he would bring war and devastation to Troy. Her parents believed this prophecy, and they commanded a servant to dispose of the baby. However, a shepherd found the baby, took him home, and named him Paris. Cassandra's prophecies were not always believed, however. When she spurned Apollo's advances, he cursed her by declaring that she would from then on be considered a liar and a crazy woman. When Paris returned to Troy as an adult, and his true identity was revealed, his parents welcomed him back as their son and a prince of Troy. Cassandra tried to remind them of her vision of the destruction of Troy, but they refused to believe her and had her thrown into the dungeon. We know what happened when Paris met Helen!
On the deportation train, Madame Schachter had a vision of fires, and everyone thought she had gone crazy. When they finally arrived at Auschwitz, they could see the furnaces, and Elie Weisel knew that her ravings were really a vision.
If you're interested in reading a novel about Cassandra, I suggest The Firebrand by Marion Zimmer Bradley. It's a really good read.