I had exactly the same problem, and I managed to make it work by running QuickBMS after dumping the entire contents of the Xenoblade .iso into its own folder. Apparently, you can't just extract a solitary .pkb file and run QuickBMS on it; the .pkb file needs to be located in the correct directory within the contents of the .iso.
You can also try running "quickbms_4gb_files.exe," which comes with QuickBMS. That's the one I was running when it finally worked.
What are you planning to do with the models anyway? If you figure out how to vertex edit them, please let me know.
You can also try running "quickbms_4gb_files.exe," which comes with QuickBMS. That's the one I was running when it finally worked.
What are you planning to do with the models anyway? If you figure out how to vertex edit them, please let me know.