Detective Senior Sergeant Nik Leigh said investigators were continuing to narrow down what happened in the crash, which is believed to have killed Mr Buis.
Officers had identified and spoken to the driver of a red Ford Falcon which was believed to have fatally hit the Dunedin father of one in Eglinton Rd on the evening of July 21, he said.
The investigation was being treated as a homicide.
The red Falcon was the subject of a Ten 7 Aotearoa broadcast last month, which called for public help to identify the driver.
However, it had largely been old-fashioned detective work which had identified the person they were looking for, Det Snr Sgt Leigh said.
"We’ve identified the driver through a number of other inquiries as well as [the Ten 7 broadcast]."
The broadcast had generated abit more public interest in thecase, which investigators were still treating as a long game — for now.
"These things can turn on a dime.
"We’re having to exercise a bit of patience at the moment because obviously if this goes to court we want to be able to present the best evidence," Det Snr Sgt Leigh said.
Investigators were still interested in talking to people who did not want to talk to police at the time of Mr Buis’ death or did not realise the significance of the information they had.
"If we haven’t spoken to them already then we’d certainly be interested in speaking to anyone else who has any information," Det Snr Sgt Leigh said.
People could also provide information anonymously through crimestoppers.
Det Snr Sgt Leigh could not give any updates on possible gang links to the killing.
Last month, he said Mr Buis was believed to have gone to the Unity Park Lookout with an associate in order to meet someone, but they were met by two cars, including the Ford Falcon, and a person they were not expecting.
Mr Buis left the car he had arrived in, and went on foot towards Eglinton Rd where he was fatally run down.
