Not sure why he would turn down the Seahawks. Could have had something to do with the offer or more than likely with control over the roster.
Over and over I read of HCs and GMs that aren't on the same page, or that the GM sees his job as defining the roster, and the HC's job is only to manage the team the GM assembles (that is very much the Green Bay way).
Clearly the way the Rams do it is as a collaboration with the HC determining the systems and types of players he needs, and the GM going out and finding them. But even on draft day, you see Snead, McVay, and all the scouts working together on deciding these picks. But, guess what? The owner is nowhere in sight.
He wouldn't even take the interview if didn't have aspirations.