apologies you had answered with your views further down the thread.
Depends on how much day to day influence he actually had -presumably even if you accept he was the boss -which is by no means clear - he wasn't picking the team or doing team talks or on the bench, nor would you have wanted him to.
If, big if IMHO, your assessment is right the fact that he failed as director of football but then does ok as manager/coach do you sack him due to how he did in his previous job?