They need to prove you destroyed evidence, you have the mens rea component with the deceptive pin code but the defense can simply plainly say they didn't want the police to read their private device.
Your example is fabricated since the justice department didn't even bring forward a specific crime they believe was committed here.
If they charged him with a crime and had evidence his device had evidence of that crime (even if in reality it didn't) that would be a more interesting question.
But again where is the crime?
>with the deceptive pin code but the defense can simply plainly say they didn't want the police to read their private device.
That's as convincing as saying you burned all the documents because you don't want people who break in to read all your financial records. It just happened to start after the SEC came knocking
> But again where is the crime?
Destruction or removal of property to prevent seizure.
CBP are empowered to search US citizens devices and, if the citizen refuses to comply, to seize that device. They'll be alleging that by knowingly providing CBP with a duress PIN he destroyed his own property to prevent its seizure.
Notably, they don't need to prove he destroyed evidence of anything.