Your srikethrough is appropriate. The sacking of the Whitlam government came about through a conspiracy by Australians (principally the leader of the opposition, the chief justice of the high court and the governor general) who helped themselves to the Reserve Powers of the queen.
Fraser's motive was the most obvious. He wanted to become PM before the next election was due. Sir Garfield Barwick was a rabid right-winger who would do anything short of actually criminal to fuck up Labor. John Kerr yearned for status to make up for his humble upbringing. He was bribed with a knighthood and an ambassadorship.
The situation was rather more convoluted and complicated than that, but this is probably the wrong thread for a mini-lecture. Suffice to say, I doubt the Queen was even aware of the plot until the sacking had become a fait accompli.