Within the span of 15 hours, the Knicks had reached a decision to acquire Toronto Raptors point guard Kyle Lowry before the trade was vetoed — at least for now — by Garden chairman James Dolan, the Daily News has learned. According to a source familiar with the talks, Dolan had second thoughts about trading for Lowry and was also — what else? — enraged that details of the proposed deal had been leaked to the media. According to several reports, the Knicks were prepared to trade Raymond Felton and Metta World Peace plus Iman Shumpert or Tim Hardaway Jr. or a 2018 first-round pick. The Raptors preferred the first-round pick, but Dolan — who negotiated the Carmelo Anthony trade with Raptors GM Masai Ujiri when Ujiri was with the Denver Nuggets — got cold feet about trading a future asset. That could open the door for the Brooklyn Nets to acquire Lowry instead. “Dolan didn’t want to get fleeced again by Masai,” was how one Knicks source put it. “They had a deal ready.” Knicks brass met following Wednesday’s win over Chicago and had decided to move forward with the deal, but by early Thursday afternoon, Dolan suddenly had second thoughts. “There are two problems,” the source said. “Dolan didn’t like that someone from his group leaked it to the media, and the other problem is the Knicks seem to have too many (people) involved with making decisions.” Since any deal involving World Peace can’t be made until Sunday, there is still a chance the Knicks may reconsider, especially if Toronto and Brooklyn get close to a deal. When Ujiri was in charge of the Anthony negotiations, he was dealing with both the Knicks and Nets and got Dolan to blink first. Dolan agreed to ship out Danilo Gallinari, Wilson Chandler, Timofey Mozgov, Felton, $3 million in cash, plus a 2014 first-round pick and two second-round picks. Donnie Walsh, who was the president of the Knicks at the time, felt the asking price was too high and that by the Knicks waiting until the trading deadline, Denver — which knew it had to trade Anthony — would have agreed to rework the deal. Instead, Dolan took over the negotiations and agreed to it days before the deadline.