Rosalind Archer, who with fellow independent director Rod Ritchie had recommended the scheme of arrangement, told the meeting that the appetite for risk among shareholders varied widely and that it had been right to put the offer before them.
Given the outcome, she said there would need to be a "strategic refresh" on the firm's future direction and how "we can all go there together."
"The company and the board have a very clear steer on what the collective appetite for exploration - and taking those kinds of explorations risks - is from the minority shareholders."
NZOG shares dropped 7.8 per cent to 59 cents. They fell almost 10 per cent on Friday, from 72 cents, when the first update on electronic voting on the proposal showed minority holders were split on the deal.
NZOG is 70 per cent-owned by Ofer's energy arm, OG Oil &Gas.
It has a small stake in the Kupe gas field and, through subsidiary Cue Energy Resources, a small stake in the Maari oil field and production interests in Indonesia. It also owns half the Barque exploration permit off the Oamaru coast and has a 15 per cent stake in the Ironbark prospect off north-western Australia where partner BP plans to drill late 2020. Cue, half-owned by NZOG, also has a 21.5 per cent stake in Ironbark.
NZOG has been unsuccessfully trying to buy into producing assets and has little prospect of finding partners to help fund its New Zealand exploration activities after the government banned the granting of new offshore permits.
Archer and Ritchie were in a tough spot after recommending shareholders accept OGOG's earlier 62 cent offer – a 25 per cent premium. Vocal opposition saw that subsequently increased to a final 74 cents, further reinforcing a perception among shareholders that the offer was opportunistic.
Archer reminded the meeting in Wellington, attended by 22 shareholders, that a common condition of a scheme of arrangement is that directors will recommend the transaction if the negotiated offer price falls within the valuation range of an independent adviser and no superior offers appear.
Northington Partners had valued NZOG shares between 62 and 84 cents.
Archer said she had no advice on how OGOG, which bought into the company in 2017, will respond to the rejection.
Chief executive Andrew Jefferies told the meeting that he, Archer and Ritchie have exploration backgrounds and are "possibly a little surprised at the vehemence of the devotion for exploration that our shareholders have shown."
He said the firm is still pursuing opportunities and will continue to do so until that strategy is reviewed by the board.
The Accident Compensation Corporation is one of the company's biggest shareholders with a 1.8 per cent stake as at August 12.
Guy Elliffe, an investment manager with the corporation, said the firm is "drawing a long bow" on investors' appetite for exploration and he urged the company to canvass investors widely during the coming review.
"All shareholders are saying, when they are voting against the offer, is that they think the price is inadequate," he said. "To extrapolate that to shareholders making a long-term commitment to an E&P strategy is factually wrong."
Elliffe also said the skills needed of independent directors in conducting such a review were not necessarily the same as the exploration and production skills that Archer and Ritchie brought to the role.
Archer said she couldn't promise a change in board structure, but said chair Sam Kellner had heard the complaints coming from shareholders.