To recover the files the admin must follow these steps:
- Sign in to dropbox.com with your admin credentials.
- Select Admin Console from the left sidebar.
- Click the Members tab.
- Under Member type, select Deleted from the dropdown.
- Click the gear icon to the right of the former member’s name and select Manage files from the menu.
- Select the option to Transfer to another team member.
- Enter the recipient’s name or email address and click Submit (the recipient must be a member of your Dropbox Business team).
This link will help transfer the user files on dropbox from one person to another
https://help.dropbox.com/business/account-transfer