1)
Is Yerushalayim called "Hashem Tzidkenu"?
1.
Radak: No. It residents will say "Hashem Tzidkenu."
2.
Radak citing Targum Yonasan: [Yes], for it will make us, who dwell in it, meritorious in front of Hashem.
2)
This was written above (23:6), but there it says that Yehudah and Yisrael will dwell serenely, and it says "Zeh Shmo"!
1.
Refer to 23:6:3:1.