Both parties appointed a custodian. Before payment, only the pledgee orders him to sell. What is the basic response?

Kitab al-Rahn: Salam, Sarf, Third-party Custody and Fungible Collateral

• A creditor’s request automatically suffices
• The pledgee has become the owner
• Appointment to custody does not itself give agency to sell
• The debt always vanishes without any sale