In the Signals Notebook, embedded document data is not included as transcripts in the experiment document, only the preview is printed.
To include the attachment's full contents use the option ‘Embed documents as attachments’ during the ‘Print to PDF’ operation. The files are added to the PDF as individual document attachments in their original formats (.pdf, .xlsx, .docx, .zip, etc.).
To view the files once you have downloaded the PDF open it in Adobe Acrobat, not the browser and click on the ‘Attachments’ button (looks like a paper clip), the list of attachments will be displayed.