The rationale is simple, the US is prosecuting, Australia is not.
It doesn’t matter where the stock is listed, the shareholders aren’t going to be too happy knowing that you are risking the entire company by going against US law. Better to have 50% of something rather than 100% of nothing. I’m not saying I agree with their stance, but I understand it. It sure would make more sense for them to operate as is and take the money earned from US players to fight this absurd new law.