The NRL coach decides which NRL players (including supplementary/development list) play reserve grade that week, and where he wants them to play. He will even tell the reserve grade coach what he wants them to work on during the game. And because the reserve grade coach works for the NRL club, rather than Wentworthville Magpies, he has to do as he is told.
Like he's got anyone better? The guy has played NRL. Even Bellamy picked him in first grade. He's surely better than most part timers.
This is the story of reserve grade teams in general.
Maybe Asi and Hands are in their positions to improve the team's defence? Plus they are both NRL squad members, so the NRL coach will decide where he wants them to play.