If the Dolphins go 10-6 on the season (9-3 under him) and miss the playoffs, Dan Campbell will be offered a head coaching job by some team next year (probably the Dolphins)
What the Dolphins do will very much affect his career, Dolphins go 4-12 at best he is going to back to being a TE coach and it will be a long time before he gets another HC shot. Dolphins have a winning season he will be an OC some where and probably be an HC somewhere within 3 years. For him it is more than a place holder.
OK, in the off chance scenario they win 10 games and miss the playoffs he keep the job.
2 things
1) This roster isn't winning 10 games
2) 10 wins will get you in the playoffs in the AFC this year
So in your off the wall, make no sense scenario he would keep his job. Now back on planet earth let's deal with reality.
For him and his career yes it means alot yes, for Dolphins fans (like everyone on this site) he is the placeholder for 12 games then he is gone