Both sides went into the sheds at half-time with the score at nil all.
Nalkutan's Azariah Soromon powered his side to the front early in the second half with two goals in the 47th and 57th.
Another goal three minutes later put Nalkutan in firm control in front of the home crowd at Korman Stadium, Vanuatu.
Dwellers' only goal came from Nigel Dabinyaba.
But the show belonged to Soromon who found the back of the net for the third time right on the 90 minute mark.
Nalkutan's win has booked them a home final in Pool A after finishing first with three wins.