1)
What is the meaning of "va'Yis'anaf"?
1.
Malbim: The Hispa'el of Anaf shows that anger eradicated (caused a final decree)
2)
Why does it say "ha'Nir'ah Elav"?
1.
Radak: This is like Asher Nir'ah Elav. Normally, the prefix Hei is in place of 'Asher' only for the present conjugation. There are other exceptions - "ha'Hikdish Shmuel", "ha'Nimtza'u Fo" (Divrei ha'Yamim I, 26:28, 29:7).
