McGregor said it was unfathomable someone could kill her son in such a heinous crime - and keep quiet about the murder for so long.
"We all spent countless hours driving around the Waikato and Auckland areas looking for him."
Police discovered Chance's body on March 10, 2019, at Lingman's rural South Auckland property in Kingseat, near Karaka.
"That was the longest two weeks of my life," McGregor said.
"Denver was a very kind, considerate, loyal and beautiful son, brother, uncle and friend."
Lingman at the trial this year admitted taking a chainsaw to Chance's body before placing him in the freezer.
McGregor said the disrespect and degradation was extremely hard to comprehend.
"I miss my beautiful son so much."
Lingman pleaded not guilty to murder and during his trial, claimed he acted in self-defence when an angry Chance surprised him at his Karaka house.
Security camera footage and Google location data showed Chance was in Karaka on February 24, 2019.
But the Crown said Chance was never armed and Lingman shot him before attempting to cover up the killing.
Prosecutor Gareth Kayes today said the jury's verdict was consistent with the idea Chance and Lingman had a pre-arranged meeting.
Drug underworld
Defence counsel Ron Mansfield said it was established at trial that Chance was a commercial drug dealer connected to patched Head Hunters members.
Mansfield said Lingman did have positive aspects of his character, and friends and family who valued him.
"But he acknowledges, frankly, that he was also involved in commercial drug dealing."
The defence still maintained a conflict erupted at Lingman's property, which must have caused either man, or both, to arm themselves.
Sadly, this conflict could only have ended with one or both men getting hurt, Mansfield said.
The public gallery at the courthouse was full during today's hearing, and Justice Melanie Harland acknowledged those present and thanked them for attending.
She said Lingman and Chance inhabited an "insidious and evil drug world" kept secret from even their loved ones.
Lingman in the dock mostly just looked ahead, his head down slightly.
Apart from the murder charge, he was also sentenced on three charges of drug possession for supply.
Justice Harland sentenced him to life imprisonment with a minimum 15-year and two-month term.
'Unconditional love'
Chance's sister Ginny O'Sullivan, based in Tennessee, recorded a statement.
Her brother was a kind man who did not deserve to die in such a gruesome and senseless manner, she said.
"His unconditional love was a beautiful thing, unwavering and steadfast."
Addressing the killer, she said: "I want you to live with the pain you have caused all of us, to your last breath and beyond."
It pained her to think of Denver watching his family from the afterlife and seeing them suffer, O'Sullivan said.
"Imagine what he could have done in a full lifetime."
