I look at what got Mac fired:
1. Team not ready to play Michigan
2. Lack of offensive production against Tennessee and Kentucky
3. Ditto for LSU
4. Ass whoop in by Georgia.
Avoid those 4 things and we will be fine with the coach.
All that contributed to his being fired.
What got him fired was the stupid idea that "death threats" were made. Making that statement without clearing it first. Having or not being willing to provide any details of the "death threats". And being an ass and not a team player with those he should have been. Finally quitting against GA in combination with the "death threats" stuff.
He had plenty of issues with his team, from the idiot 9 to lots of injuries, some of these would have excused some of the team not performing.
Just my take on what really caused his being fired and him not getting his entire buy out either.