Dixon was also charged with assaulting a friend of Mr Sinke, also at the bar.
Police said Mr Sinke was struck and rendered unconscious after an ``altercation'' with a man at the Sub Culture nightclub about 3am.
At Dunedin Hospital, surgeons had to remove a bone flap to ease brain swelling and Mr Sinke was kept in an induced coma.
Dixon hit the headlines around the world after he released CCTV footage of England rugby captain Mike Tindall embracing ex-girlfriend Jessica Palmer on a night out in Queenstown with teammates during the Rugby World Cup.
The player had married the Queen's granddaughter Zara Phillips only six weeks before.
Dixon was fired from his job and charged with accessing a computer system and dishonestly obtaining video surveillance footage.
He has denied the charge.