Mr Beard said yesterday said staff were hunting for two men who checked in with Mr Gillman-Harris about 8am on Saturday.
The men were captured on the motel's CCTV system and appear to be younger, wearing baseball caps and hoodies.
The pair were later seen leaving the motel in Mr Gillman-Harris' blue Range Rover Vogue shortly before Mr Gillman-Harris approached motel staff asking for help.
He had been violently assaulted and was rushed to hospital, where he died.
The men's relationship to the victim is still officially unknown, although motel staff reported that Mr Gillman-Harris had referred to them as his nephews.
Police have released images of the men suspected of being involved in the attack. Photos / Supplied
The victim had spent Christmas Day with family members in Wellington before travelling up to Auckland on Boxing Day. He also had links to the North Shore, Kaikohe and the wider Northland region. The vehicle he drove to Auckland was a silver Mazda 626 with the number plate WJ2383.
"This is a tragedy for the Gillman-Harris family," Mr Beard said. "It's the festive season, but it's turned to a state of tragedy for them."
Police acknowledged that as well as needing to identify the two men seen leaving the motel, they also wanted more information about the victim himself. He was a very private individual.
"Mr Gillman-Harris lived a private life and we are interested to hear from anyone who knows anything about him and could shed some information on the life he lived."
Records show that Mr Gillman-Harris had a love of cars owned at least two Rolls-Royces, a BMW and the blue Range Rover Vogue he was driving on the day he died.
The Herald also understands he worked as a team leader assistant at the KiwiRail freight terminal in Southdown.
Mr Gillman-Harris' nephew, Ihaia Harris, said the whanau were set to meet within the next few days. Until the family's elders had met, they would not give any details about their relative.
Family and friends were, however, supporting each other after the tragic news.
"We're shocked. This is totally out of left field. What can you do but just be there for one another?" Mr Harris said.
Contact police on (09) 302-6400 or anonymously on CrimeStoppers: 0800-555-111.