A woman has now come forward claiming she was told what happened.
In an online post, family friend Beverly Jackson wrote she told police the killer's name and gave details about where to find the body.
"Milton did make it to Whangamata that night. He was shot in the head by a certain person named PW. He was killed in Whanamata [sic]," she wrote.
"Milton was shot in the head, buried near a drug patch and his car driven to Rotorua forest and abandoned."
Ms Jackson said "several people" had passed the same tip to police.
Mr Channing's family were too upset to speak about developments in the case.
Their son was described by friends as a popular man from a respected Taupo family.
Bay of Plenty field crime manager, Rotorua-based Detective Inspector Mark Loper, said police were making inquiries into the case.
"At this point, there is nothing that we can advance," he said. "It's a matter of resourcing and we will get to it when we can."