The information entered in the PCI field is stored in a secure environment outside of Freshdesk.
The Virtual Private Cloud (VPC) used to store the encrypted PCI data is a service on its own and does not have any peering to any of the Freshdesk’s VPCs. The stored data will not be read/written directly from Freshdesk or any of its subsystems.
When agents/admins wish to enter or unmask the data in the PCI field, they will be hitting the secure environment's API directly to store or retrieve encrypted information.