Rose gold???I tend to think the Dolphins official colours will be red & white with gold, and that the black we're seeing is just for off-field / merchandising purposes. Look at the current NRL clubs that use black or other colours for their polos, training gear, ect.
For mine, WC Pirates should be gold and black with red.
Dolphins jerseys will, I'm confident to say, be mostly red or white (depending on whether home or away jersey), so Pirates going with the mostly gold or black jerseys wouldn't clash with the Dolphins.