The ABC should have been worried the second the ALP wrongfully awarded them the "Australia Network" contract.
This was a sign that the ALP saw the ABC as a political friend. If the same act had been done between an individual and the ALP, it would be deemed corruption.
The ABC took this money as a present from the ALP.
The ALP started corrupting the ABC through funds. Its just that the ABC didn't care if it's being bribed. Only blackmailed.