Hidding information is seen as obstruction, usually illegal in itself, and shows intend behind whatever illegal and anti-trust violations happened... No idea why this is so hard to understand...
If an unknown entity bursts violently into your office, locking your computer seems a very reasonable security precaution to take.
I would assume the French legal system has methods like most democracies to require a company to retain data and request a copy of that data. We're talking about a corporate office here, not a drug packaging center hidden in the basement of a suburban home where everyone hurries to flush narcotics.
The whole chain of command involved in this could go to jail for obstruction of justice, maybe even conspiracy to defraud the US (depends on the interpretation of fraud).