Having never been to either ground, and therefore know nothing about the facilities at either Kiwitea or Fred Taylor, I do question why Waitakere should be expected to voluntarily move away from the venue they have been playing their home games at all season, and effectively give up the home ground advantage they earned by finishing on top of the league.
I do agree that Douglas Field would be a better option than Fred Taylor but being the home team, they don't have to give up their final on their ground.