Maybe they simply said, "Mr. Trump, we have credible witnesses who will come forward with complaints which will be reported worldwide and be very damaging to you." ... or.... Maybe they said "Mr. Trump, we have the ability to manipulate your bank records and bring charges..."
When you live well, you are not untouchable if those who control the courts and the media bring their guns to bear.
Justified or not, the head of the IMF just got pulled off a plane and charged with a series of felonies which will destroy any reputation he has and guarantee he will not become President of France.
Think about it, and then go watch Emeny of the State (or even Fahrenheit 451 again.
People who have a lot, also have a lot to lose.