As mentioned by several users- i have problems with file type.
After analyzing your code and the output i came to the opinion that
isn't any template to generate file specific methods in Document,
or there is an logic error [to initIsFileProcess() isFile come as TRUE].
I checked up all steps of code generation and saw that in the document repository isFile property was set right (as TRUE).
It's not a problem with mondator, probably it's in Extension\Core