I need to convert incoming TIFFs to PDFs in scripting, so I've tested tiff2pdf. I have actual (4.0.6) version of LIBTIFF, installed with apt. It did well with some samples produced by scanner, but it failed with examples from this page.
The PDF was generated, but the pages are empty when viewed with ImageMagic or Print Preview under Ubuntu, on Acrobat (in Windows) it shows erros that the PDF is invalid.
Is there a bug in current LIBTIFF considering multipage tiffs? Unfortunately the 'Official' bugzilla is down, and I've found no reference where is the actual version... Or those examples are somehow 'non-realistic' and I should expect no scanner to produce them?
Use -n as flag, it worked for me with the same file from your example, see https://www.systutorials.com/docs/linux/man/1-tiff2pdf/