There's an important thing that the CEO provides that no AI can: the acceptance of risk.
On a day-to-day basis the CEO makes decisions, ignores expert advice, knocks off early for tee time, etc. For this work they are wildly overpaid and could easily be replaced by having their responsibilities divvied up amongst a small group of people in leadership roles.
To see the true purpose of the CEO we need to look at a bigger scale - the quarter-to-quarter scale. What could be bigger than that in the world of the MBA?
Every quarter the CEO must have the company meet the financial performance expectations of the board/owner(s)/shareholders. Failure is likely to result in them losing their job and getting a reputation as an underperformer, thus ruining their career. If the company does poorly or those expectations are unreasonably high then the CEO must cut corners in the operation. This of course hampers their ability to meet expectations later, but they'll make it through this quarter.
When (inevitably) too many corners have been cut something catastrophic will happen. Either the company's reputation will go to shit with customers slowly, or a high-profile scandal will blow up in the company's face.
This is the moment when the CEO provides their most valuable service: to fall (or be pushed) onto their sword. The CEO is fired, ousted, or resigns. This allows the board/owner/shareholders to get a new face in and demand that they fix the most egregious issues, or at least the most glaring ones that don't cost too much to fix.
This service cannot be provided by an AI. Why? Because the AI is a creation of the company. If it is used as a scapegoat it solves nothing. The company is pointing at their own creation and saying "see, that's the problem". It's much more effective to point at a human they didn't make and scream that that person made a mistake.
She specifically said that the new tech would "increase" and "turbocharge" fraud. She did not use that example as some new kind of fraud, only that it could be done more effectively or more easily.