Hiring Mancini would be, without any stretch of the imagination, the worst decision the management could take...to say nothing of the ramifications it'd have in terms of image and morale. This is an extremely poor coach, both in terms of ability and attitude. He is weak-willed (cannot control a dressing room) and just has a very distasteful personality, in general.
Can you imagine?
One of the most outspoken (and deluded, he actually believes Inter won that faxed scudetto fairly, I'm sure) people against this club attempting to lead it? It'd be a laugh to see him try and handle the team, especially the veterans.
This is to say nothing of the wages he'd likely demand.