1)
What is the difference between Yeshu'ah and Ezer?
1.
Malbim: A Moshi'a acts all by himself. An Ozer helps a little; the one he helps is primary. Giv'on asked that we [alone] save them, or at least help them.
2)
Why does it say here "Nikbetzu"? Verse 5 said "va'Ye'asfu"!
1.
Malbim: Asifah follows Kibutz. They already Nikbetzu (9:2); now they merely needed Asifah against Yisrael 1 . For the Giv'onim, this was the first agreement to oppose them, so it says Nikbetzu.
1
I.e. the Asifah in verse 5 was to fight Yisrael. It says that they camped and fought against Giv'on! Is this still not considered Asifah?! Perhaps Giv'on said this before they started fighting. (PF)