This paragraph from same article should also be noted. Mavs just didn't evaluate the importance and value of Brunson correctly. Even if they could make their offer, it would be lower than NY one.
In the end, it didn’t matter that the meeting never took place. As a league source close to Brunson said, “You always want to feel wanted.” Perhaps only Brunson knows to what extent Dallas’ hesitations to retain him — either by extension or by outbidding the Knicks, which Dallas reportedly did not plan to do even if given the opportunity — affected what was, at that point, his certainty that he would leave for New York.
In the end, it didn’t matter that the meeting never took place. As a league source close to Brunson said, “You always want to feel wanted.” Perhaps only Brunson knows to what extent Dallas’ hesitations to retain him — either by extension or by outbidding the Knicks, which Dallas reportedly did not plan to do even if given the opportunity — affected what was, at that point, his certainty that he would leave for New York.