[StillBored]

In this case, yes that appears to be what happened. The low level employees reportedly raised the issues.

From TFA:

"But even as employees frequently raised alarm, the company’s top leaders did little to prevent Walmart from being involved in bribery and corruption schemes."

Which is why no-one is going to jail, if it were just a low level employee you can bet they would be charged/fired and jailed. But since it went high in the mgmt chain, they likely can't just pin it on someone. The records likely got looked at, discussed off the record, and then got ignored without anyone's fingerprints on them.