The Nashes compromised, intimidated into submission by Yusuf Zuck, and truth be told, they were truly afraid of Tyler Nash returning, so with Knox Nash as the Family Head and Yusuf Zuck's support from behind, there would be no more disturbances within the Nash family.
In plain terms, all the clan members of the Nash family wanted was wealth, and they didn't wish to experience any of those violent conflicts.
Last time, Tyler Nash had already scared them terribly. Tyler had even killed his own father and older brother, and used their children as leverage, so they preferred Knox Nash as the Family Head rather than having that madman, that monstrosity come back.