What if the pig is actually Kamapua, the god of pigs. Pua is short for Kamapua.
In Maui the kukui is a symbol of enlightenment, protection and peace. It was said that Kamapua'a could transform into a…en.wikipedia.org
“He also is recorded as having many run ins with other chiefs and other influential people”
Maybe after Moana was chosen by the ocean, the gods sent one of their own to watch her and try to convince her to sail on the sea to restor Ta’ Fiti’s heart.