It can be proved in court that this transcation was coercion
Explanation:
Coercion if proved does not bind people into contracts and they are then not liable to fulfill them.
As such if Marcus is able to prove that he was indeed coerced by Kristoff to buy his collection of shoes in fear for his personal safety he would no longer be obligated to abide by the contract and Kristoff will be liable to be punished under the court of law as coercion is a major offense in trade deals and is taken to be a crime and not a civil offense.