Will they dwell only in Tziyon and Yerushalayim?
Rashi: Those who remain there will be Tzadikim.
Radak: Yes - Melech Ashur will seize the other cities of Yehudah, because they did not trust in Hashem.
Malbim: Even though you did not want to listen and dwell calmly without doing anything, there will be found in Tziyon (the place of the kingdom), and in the entire city of Yerushalayim, people who did not rely on Egypt's help. They will dwell and not need to flee.
Why does it say "Bacho Lo Sivkeh"?
Rashi: You will not need to cry to request from Hashem. He will answer your scream.
Radak, Malbim: The nation in Yerushalayim who did not leave to request help from Egypt. You will not cry like the others will; Hashem will have grace when you scream.
What is the meaning of "k'Sham'aso Anach"?
Radak: When He hears your scream, He will answer you. When Chizkiyah tore his garments and covered himself with sackcloth and came to Beis Hashem to pray, Hashem answered him via Yeshayah - "Al Tira Mipnei ha'Devarim Asher Shamata