JJ Daigneault vs Robinson is a moot point. Robinson wants to spend a lot of time in Florida, at his home. He doesn't want to be an assistant coach.
Note his role in St. Louis isn't as an assistant coach, its as a consultant, meaning he will work from home and fly in for a few days or a week at a time and then go back home. He's not full-time on the road with the team. If he wanted to be a full-time assistant he wouldn't have left San Jose.
While I'm no fan of Daigneault, there was no possibility of canning him and hiring Robinson. Robinson doesn't want that job. (I'd still replace Daigneault with someone else though).