1)
Why does it say "Charev" and "ha'Neshamos"?
1.
Malbim: Charev applies to buildings, and Shemamah applies to the entire land, i.e. other cities of Yehudah and Chutzos Yerushalayim. It is a higher level than Charev.
2)
What are "Chutzos Yerushalayim"?
1.
Malbim: It is in back of the houses.