It isn't. In Esther, God doesn't say one thing, do one miracle; and not one thing happened because of a supernatural event. Other OT books at least, are written having these things distorted or not. The NT the same thing with less variants.Didn't you say the Book of Ether was not of God?
There is at least of semblance of inspiration with errant or not. Esther is about the Jews killing others for no specified crimes. At least the Canaanites knew that they stole land.