The discovery of Taumalolo is one of the great scouting success stories. He was with a Papakura Sea Eagles junior side who visited Townsville for games against local high schools in 2007. Zammit had come down to watch other prospects but couldn't believe what he saw from the back-rower.
"He was up against guys three or four years older but standing out - a rare talent," Zammit says. "He was man-handling the 16-year-olds. I knew I couldn't let him go back to New Zealand without signing him - otherwise I wouldn't see him again."
The team, however, were due to return home early the next morning but Zammit would not be dissuaded. He arranged a meeting for later that evening and rushed back to his office.
"I did up a contract for four years and then went to see Jason and his father," he says. "We met in a pizza parlour."
It's an encounter Taumalolo remembers well.
"I was just sitting there thinking about how good the food was. I thought I would just come back for another game but, when he said he wanted to sign me ... it was a life-changing moment."
It was also a lot to take in. While his peers were preoccupied with PlayStation, pimples and Pepsi, Taumalolo had to think about a new life in a new town.
"That is something a normal 13-year-old wouldn't go through, obviously," Taumalolo says. "At the time, you don't really know what it all means."
Zammit knew. As part of the deal, he also signed Taumalolo's brother Warner and a contract was struck by midnight.
"I was surprised he had not been picked up earlier but I knew he would be," Zammit says. "We couldn't muck around."
Taumalolo left New Zealand soon afterwards, completing his schooling in Queensland. He prospered on the field, becoming the third 15-year-old after Justin Hodges and Will Hopoate to be selected for the Australian Schoolboys team, but it wasn't easy to adapt.
"I was pretty nervous when I had to leave home," Taumalolo says. "And it was a gamble from [my parents] to let me go, especially at a young age to make a career out of league. I was staying with a family I had never met and trying to adapt to how they live. The [hot] weather was pretty hard and Townsville is quite small - I didn't really like it at first."
Zammit told his colleagues he had signed the next Sonny Bill Williams - "they all mocked me" - and comparisons with SBW reached the public arena after Taumalolo became the youngest first-grader in Cowboys history (17 years and two months) in 2010.
His career has flip-flopped since - he spent prolonged periods of last season playing Queensland Cup - but it was always a sense of when, not if.
"People forget Jason is still only 21 but has played 60 NRL games and been in the competition four years," says Kiwis coach Stephen Kearney. "There are going to be ups and downs but he's been great this year."
It feels like Taumalolo has arrived and he averaged 125m in his 23 games this season.
"He's a good kid," says Zammit. "He's had to learn about work ethic - which everyone does - while also deal with a lot of hype. But he could be one of the best forwards in the game. He's big and powerful but very light on his feet with great footwork through the middle."
It means he's hot property, with a bidding war about to start for his services in 2016.
But the quietly-spoken Taumalolo comes across as humble - the only ostentatious touch might be two gold front teeth but they are a Tongan cultural tradition he had done when he was eight.
He talks about lessons learned from room-mate Simon Mannering and sounds genuinely honoured to be playing for his country.
"It's [been] worth the wait," says Taumalolo, who was 18th man for the Kiwis in 2012 but didn't debut until this year. "I knew my time would come, I just didn't know when. A lot of boys tend to go on a bit of a holiday after the NRL [season] but when Mooks [Kearney] gave me that phone call, I was training every day. I wanted to make the most of the opportunity. Being in the black and white is probably the proudest moment of my career."
It so nearly didn't happen. Taumalolo was pressured to align with Queensland in 2012 and received phone calls from coaches Mal Meninga and Tim Sheens. It was even reported he had pledged his allegiance to the Maroons and Australia.
"[Origin] was pretty tempting, especially when a legend like Mal Meninga was calling to talk to me," Taumalolo says.
"It was one of the most nerve-wracking things I have ever been through. [But] I stayed with the black and white because my heart was at home."
It means the Kiwis pack should be an intimidating prospect for years to come containing the likes of Jesse Bromwich, Tohu Harris, Kevin Proctor and Martin Taupau.
"He's one of those guys who is so hard to stop, which creates so much momentum for the team," says Kiwis wing Gerard Beale. "Watching him hit the line and carry a few players with him - it inspires you."
Taumalolo is trying to not get carried away.
"I've made it a long way in my career but there's still a long way to go," he says. "I was one of the lucky ones to be picked up at such a young age. It's only going to get better from here."