Walker was eventually the last one dismissed for 53 off 50 balls, including nine boundaries.
"If we all batted like that," Carroll lamented.
"We all got starts but no-one kicked on.
"We obviously came up probably 100-150 runs short; it was a 300 wicket."
In reply, NPOB picked up where they left off in their Taranaki one-day final victory over Woodleigh the previous weekend, as veteran Jamie Watkins (65) and teenager James McDougall (64 not out) compiled another big partnership.
NPOB scored at over five runs-an-over to reach the meagre target in the 29th over.
"Watkins is not the most technical but he knows how to play that deck he swung through the line and clean," said Carroll.
"That other player [McDougall], he's a class player."
Scoring at better than a run a ball, the lethal pair collectively hit 12 balls to the boundary and put six more deliveries over the rope.
NPOB will now travel to Palmerston North to play the final of the Central Districts one-day competition for a spot at the national club finals. Heading into January, the Porter Hire Premier 1 teams will play a 110-over format competition, while the Premier 2 teams will play a 40-over format.
There will also be the finals of the combined Twenty20 competition, while the Active Physio Wanganui representative team will play their remaining Hawke Cup matches against Manawatu and Hawkes Bay.