I don't understand the criticism against Australia.
For South Africa to qualify, Australia had to win 3, with South Africa, India and Pakistan winning 1 each. If Australia deliberately lost to Pakistan to keep South Africa out, then yes that would be unethical.
As it was, Australia did not throw the game. They did their best in the field and started the run chase going for the 150. After they lost wickets, they knew they had to get the 112 to qualify for the semis which is based on THREE matches in the Super 8s. It is like a Formula 1 driver who has got enough points from the previous races and just knows they have to bring the car home in 1 piece to get the points to win the title. Do you see that as unethical? I would think that if you crashed your car going for the win in the last race it is pretty stupid. If Australia didn't make the semis because they were going for the win, I would think that is pretty stupid too.
If the matches were played simultaneously, Australia would have played the same anyway.