This FinaleScript exports just PDFs, works with v25.5:
Batch Process Folder
Graphics tool
Menu item “Export Pages”
Popup “PDF”
Check “all”
Press “OK”
expect to return
Close
End
EDIT
To also process subfolders:
Batch Process Folder and Subfolders
Graphics tool
Menu item “Export Pages”
Popup “PDF”
Check “all”
Press “OK”
expect to return
Close
End