He said, when he asked McDonnell if there were Head Hunters members in a gym group he'd been with in Rarotonga, McDonnell replied: "Maybe".
Asked if he'd been in Rotorua on February 16 to 17 last year, McDonnell said he wasn't able to say accurately.
"I showed him stills from service station footage and asked if he could identify who was in the pictures," Mr Tapsell said.
"He indicated it was him. He asked if he was getting done for the kidnapping of that fella."
After that, McDonnell exercised his right to remain silent.
Detective Stephen Burborough testified about a conversation he had with Dwyer, who admitted he'd been a member of the Head Hunters gang for two years.
During their conversation, the detective told Dwyer he was aware of what had happened on the businessman's boat involving Dwyer's partner.
Dwyer's response was a reference to the businessman using a derogatory term.
"He said he went to [the businessman's] industrial yard looking for him," Mr Burborough said. "He wanted to give him a kicking for what he'd done."
Dwyer denied being at the businessman's lake retreat from where he was allegedly kidnapped.
The conversation was not formally recorded.
The jury heard from two officers who dealt with Kane. One arrested him in February 2015 for unlawfully possessing a firearm that had been found in his bedroom. In March 2015, the second officer charged him with kidnapping. On both occasions Kane maintained his right to silence. Christian also refused a formal interview.
The trial is into its fourth week.