Would control fraud work in a company as big as Amazon? If you're that big, then there's a huge probability of a whistleblower or unhappy ex-employee exposing you.

When Wells Fargo set incentives that were impossible to meet without defrauding customers, yes, they got caught. They fired thousands of tellers.

Absolutely. The bigger you are the easier it is to claim plausible deniability for each of the "isolated" incidents. If the executives will even meet the people who they've put in this position, it's easier to lose or just never hear the complaints and red flags.