Does SOX protect a whistleblower employed overseas by a subsidiary of an American company?

Boston Scientific (BSC) was an American company that manufactured medical equipment. The company had its headquarters in Massachusetts but did business around the world through foreign subsidiaries. One of the company’s subsidiaries was Boston Scientific Argentina (BSA), and it was there that Ruben Carnero began working. His employment contract stated he would work at BSA’s headquarters in Buenos Aires and be paid in pesos. Argentine law was to govern the contract. Four years later, Carnero took an assignment to work as country manager for a different BSC subsidiary, Boston Scientific Do Brasil (BSB). Carnero frequently traveled to Massachusetts to meet with company executives, but he did most of his work in South America.
About a year later, BSB fired Carnero, and BSA soon did the same. Carnero claimed that the companies terminated him in retaliation for his reporting to BSC executives that the Argentine and Brazilian subsidiaries inflated sales figures and engaged in other accounting fraud. Carnero filed suit in Massachusetts, alleging that his firing violated an American statute, the Sarbanes-Oxley Act of 2002 (SOX).
Congress passed that law in response to the massive fraud cases involving Enron, Arthur Andersen, and others. The law was passed primarily to protect investors, but included a “whistleblower” provision. That section was designed to guard employees who informed superiors or investigating officials of fraud within the company. The law allows injured employees reinstatement and back pay.
BSC argued that SOX did not apply overseas and the District Court agreed, dismissing the case. Carnero appealed.