"We were to tell these 26 boys they've got no rugby for the season," he said. "There was a few boys in tears because they love to play rugby, as you did when you were 13-14."
While the team could now play in Manawatu, what was once a healthy 12-team local grade only a few seasons ago had evaporated, he said.
"We're trying to build our 1st XV up and there's no development there whatsoever. [WRFU] should have put a stop to it."
WRFU chief executive Dale Cobb said they were "a bit powerless" as the exodus of schools who preferred placing their teams in the Manawatu competition was too strong, having started with power school Wanganui High School 3-4 seasons ago and followed shortly thereafter by the Collegiate youth teams underneath their 1st XV.
"We were still tasked to offer the same options but we couldn't because we had a fragmented competition."
While the union's focus was developing grades with depth, those top schools wanted their teams to play for higher honours, Cobb said.
In response, WRFU has set up the six-team under-14 grade with an 65kg weight limit on Wednesday afternoons, but after a parent had raised concerns over the value of that, Cullinane pulled their team out of this week.
"Parents aren't seeing the greater picture. So we've lost a team already in a competition that was viable and equitable," said Cobb.
"I've been criticised by some schools for not having the 'balls' to demand that schools stay, but I can't do that.
"It's not Joe Public making these decisions, it's the heads of the departments making these decisions.
"We're certainly not giving up the ghost. Still hopeful of salvaging a lower grade competition."
Counties U15 coach James Woon said he contacted Te Kura Kaupapa Maori O Tupoho for permission to play under their banner because at least some of his players were current or former students.
"We had to go under a school name. I do have kids from 4-5 different schools.
"A few days ago we didn't know if we were going to be a team.
"Because there's no local competition, everyone has to go over there. It's all about the kids really."
Cullinane's head of sport Hayden Hepburn was unable to respond by press time as he was attending the tangi of kaumatua Morvin Simon.
In discussions with their neighbouring Heartland unions Wanganui, Wairarapa Bush and Horowhenua-Kapiti, the professional Manawatu union has actively expanded their secondary school competitions to 74 teams, playing from Premier 1 down to an Under 14 B grade.
Of these school teams, 43 come from Manawatu, 15 from Wanganui, six each from Wairarapa and Horowhenua, and a handful from Central Hawkes Bay.
Cobb said if anything, playing in expanded grades put more drain on WRFU resources, as on a given weekend they might need to find 8-10 referees, already in short supply in Wanganui, to cover local schools playing at home against visiting opposition.
There is also the prospect of the most promising teenagers being poached by bigger Manawatu schools after they regularly take the field in front of scouts in Palmerston North.