During cross-examination, defence counsel Judith Ablett-Kerr QC challenged Det Sgt McCloy about his inquiries with that person and whether the man told the officer he received a Facebook message call from Samson on the night when Wilson was killed.
Det Sgt McCloy agreed he was aware of the call — he had asked the person for his phone, but was turned down.
"I just talked to him and tried my best to convince him to give it to me.
"He was very reluctant."
Ablett-Kerr asked if he considered the call important in a serious case like a murder investigation and questioned why he did not use the Search and Surveillance Act 2012 to obtain the cellphone.
Det Sgt McCloy said if he had "the grounds" he could have seized the phone, but he did not. He also confirmed the man had refused to sign his statement.
Earlier in the day, Detective Regan Fahey gave evidence about items found in a car which the Crown believed was connected to the case.
Among the items were children's clothes including a blue ankle sock and Nike trousers which had a blood-like substance on them.
A black wallet with several cards was also found.
One of the cards was in the name of Sam Samson, Det Fahey said.
ESR forensic scientist Timothy Power told the court about the Y-STR testing he conducted on some of the evidence to identify whether any male DNA was present in the samples.
Analysis of a combined swab of Miss Wilson's left breast revealed a small amount of male DNA.
It was 640 times more likely to have originated from Samson rather than an unrelated man selected randomly from the general population, he said.
Power also conducted the same test on a bloodstain found on Wilson's neck.
However, the result indicated the DNA detected came from more than one male and therefore was not suitable for comparison.
