I really doubt he had a ton of say in it, at that point it was all a scramble to get someone remotely qualified, less about tailoring a perfect match between the HC and team philosophy. After York and Baalke drove out Harbaugh, decided it was a good idea to promote Tomsula, and had that one blow up in their face I think pretty much the two qualifications they were looking for in a head coach were:
1. Is he a "big name" coach? After driving out an experienced "big name" coach, promoting a complete nobody, and in doing so making themselves look like complete idiots it was pretty obvious Baalke and York weren't going to go dig up another unknown and even further their status as laughing stocks of the NFL.
2. Is he willing to play for us after the way we treated our last two head coaches? The way York and Baalke did Harbs was dirty and, despite the fact that he was a bit of an idiot, they really played Tomsula pretty dirty as well. Not exactly an enticing work environment.