Open the dbx file corresponding to the destroyed folder in MailNavigator.
Select the restored messages and export them to separate eml message files using the menu command: Message | Export to Separate Messages Files...
Create a backup copy of the dbx file corresponding to the destroyed folder.
Clear the folder by deleting the dbx file corresponding to the folder.
Start Outlook Express and let the program OE create a new dbx file corresponding to the deleted folder (click the folder name in OE).
Select all restored eml files in Windows Explorer or other file manager.
Drag the selected eml files, and Drop them into the target folder in Outlook Express.