Origin of Name Paragraph 

I found this paragraph confusing.
1) Why was the sentence offering a translation changed to tell us that the name "literally means" exactly the same word that was just used? One would be better off removing the reference to the name's meaning entirely. As is this is a redundant piece of information.

2) Are Akua-ino supposed to be equated to ghosts and goblins here, or are they haunting the island at the same time as the ghosts and goblins?

Suggested rephrasing (assumptions - previously offered English rendering was accurate, Akua-ino haunted the island in addition):
The name Lānaʻi is of uncertain origin, but the island has historically been called Lānaʻi o Kauluāʻau, which can be rendered in English as "day of the conquest of Kauluāʻau." This epithet refers to the legend of a Mauian prince who was banished to Lānaʻi for some of his wild pranks at his father's court in Lāhainā. The island was haunted by Akua-ino, ghosts, and goblins. Kauluāʻau chased them away and brought about peace and order on the island, and was in consequence restored to the favor of his father.