What will it take for Tony to just concede and say "You know what? I ain't cut out for this. Someone else should run the business and creative whilst I pay for it"?

It's not like he has to give up full control. He can still have the final say. Even Vince had to give creative control to people better at it than he was. There's no shame in admitting you suck at something and need help. His skills just lie elsewhere.