FWIW, America has used journalists and students as spies, as has every other country.
I have no idea whether this lady had a relationship with US intelligence, but it is not logical to just assume that the charges are completely bogus.
I find the fact that the charges changed from 1) buying a bottle of wine, to 2) not having press credentials, to 3) espionage, to be a good indication that espionage wasn't the actual crime.