Synthesizing the data thus far, here's a draft of how I think it all went down...
1) Fox looks at team trajectory, considers pt 2 of his career arc. Refuses early extension for for max influence to force some changes, calls in Klutch muscle.
2) Kings FO gets nervous, sees trade deadline approaching, considers recent performance and current period of max value of Fox, considers team needs and assets, and balances against risk he'll walk for nothing. Klutch guy is a d-bag.
3) FO chooses the risk-averse path, makes Fox available, and gives his representatives a courtesy heads-up.
4) Fox a bit surprised, didn't actually want to leave, but recognizes there may be greener grass. Does team a solid by saying he'll go anywhere, to help them get the best value for him.
5) Cats out of the bag, too many people have leaked, so Fox cops to SA being his strongly preferred destination. This reclaims negotiating power and reduces FO chance to be opportunistic at his expense, ensuring he doesn't waste time in the boondocks when he wants to be in San Antonio.
6) Kings get the best deal they can with their limited bargaining power, but not the very best, because bringing back Castle would make Sac a rebuilding team and they'd lose DDR. Ultimately, Fox goes where he wants, San Antonio gives up frustratingly little for the deal of the century, DDR stays, and Huerter gets a fresh start,
Can't wait to see what number 7 is!