Duress can take many different forms.
Here’s a hypothetical, based on a real case. In WWII Greece, a family is willing to pay a princely sum to a man who, at great risk to himself, successfully smuggles the family to safety.
After the war, the family (survivors) sues to get the money back, claiming duress and offering, as evidence, the huge amount of money paid for the service.
The court ruled against the family. The contract was valid, and the court would not deem to judge whether the consideration paid for the service was excessive. Any amount of consideration was enough to create a contract, and the court said “even a peppercorn” was enough to create a bona fide contract.
So how do we know that this type of payment wasn’t made to secure safe passage to South Africa? And perhaps the smuggler risked his life. How much is his life worth — as much as a painting?
I've no particular problem with the courts ruling, we aren't going to undo the harm of that era, I simply found Liz's position interesting.
On the one hand the painting is worth a great deal of money, and clearly she turned out to be in the right legally.
On the other rich, ill, aging, and it's imo on the wrong side of the moral issue.
Make a good TV drama.