The reason the deal is not done is because the front office will not meet Dak’s terms. Whatever terms (guaranteed money, years, clauses) Dak is willing to sign for-the front office is not offering. Deals work both ways. If the deal does not happen (and both sides were honestly working on a deal), it just means both sides could not agree to mutually agreeable terms.
I’ve seen some people suggest that Dak just won’t sign any deal with Dallas cause he feels disrespected or that he feels he has a better chance winning with a new team. I have to admit laughing a lot at those childish suggestions.