Generally, Aspose APIs may not support reading/opening restricted files that require access permissions or other credentials. It seems that your file is a kind of restricted file that does not contain permission info or encrypted data, but relevant data may be present on a server, and MS Word has to fetch it with a certificate when you open the file manually.
In any case, one of my colleagues from the Aspose.Words team will get back to you to provide more details and assist you accordingly.