1)
Was Tzidkiyah ben Yehoyakim? The previous verse calls him Ben Yoshiyah!
1.
Radak: The verse intent takes effect on it Tzidkiyah was Ben Yechanyah. Yechanyah called his son Tzidkiyah, like Yechanyah's uncle Tzidkiyah.
2.
Malbim (15, according to Mahari): Yes.
3.
Malbim (Melachim II, 24:17): Vayikra Rabah 19:6 says that Yehoyakim had Bi'ah with his father's wife. If Tzidkiyah was born through this, he is called Ben Yoshiyah based on 'appearance' (Yoshiyah's wife gave birth to him); he was truly Ben Yehoyakim! However, Tzidkiyah was a Tzadik; we should not say that he was a Mamzer.
