His medical exemption is valid, its his visa that got denied. He had to apply under a different visa to enter the country. The other 3 players who entered the country holding a similar visa probably did not receive exemption on the grounds that they had covid infection within the last 6 months.
The problem here is that state government(Victoria) considers covid infection within the last 6 months as a valid medical exemption to enter the state however border officials don't consider that exemption as valid enough reason to enter the country on his current visa. They offered him a chance to switch his visa but the state government refused to sponsor him.
They actually did offer him to change his visa. The border contacted Victorian government to see if they would sponsor him but they rejected hence his medical exemption did not qualify for any other visa so they had to deport him.
真係以為自己GOAT大撚晒咩