"What the circumstances are which may have caused those injuries we do not know."
Mr Quayle was captured on security cameras at 2.15am walking with a female friend. The pair had been out with colleagues after finishing work about 11.30pm and had been walking home, but split up and walked down different streets.
Mr Quayle was found 50 minutes later, just 200m from where the security camera filmed him.
Police were collecting further CCTV footage from cameras near where Mr Quayle was last seen and where he died in the hope it will help them piece together the missing 50 minutes.
Mr Kinbacher hoped members of the public might also be able to "fill in the blanks".
Police had spoken with several people including Mr Quayle's colleagues and family members to establish the series of events leading up to his death.
"It's obviously important for us to build up a better picture of what has occurred," he said.
"We have an hour-and-a-half window where this gentleman travels only a short distance, and he was travelling towards his residence. It's somewhat unexplained what has occurred between those two relatively short distances."
Mr Quayle's parents and brother, who is also based in Cairns, could not be reached last night.
His cousin Claire Farley paid tribute on Facebook last night.
"RIP Philip Quayle my little cousin. Words can't describe how sad it is to hear of you passing so soon, too soon," she posted.
As news of Mr Quayle's death broke yesterday, friends also paid tribute to him.
Amber McIntosh said Mr Quayle was a "beautiful human".
"Our world down here has lost your amazing, unique and always caring soul today, I know my little world definitely has," she said.
"No doubt you have already made friends and chatting their ears off where ever you are. Very sad day today. See you again soon Phil."
Mr Quayle grew up in Nelson, attending Nelson College. He was working in hospitality in Cairns and had lived in the city for a number of years.
In 2013 he told a friend on Facebook that he enjoyed living in Australia.
"Life in the tropics is pretty hard to beat," he wrote.