Code Coverage Fuzzing Microsoft Office using WinAfl

Question

I am looking for the ways to fuzz Microsoft office, let's say Winword.exe. I want to know which modules or functions does parsing the file formats like RTF,.DOCX,.DOC etc....

Yes i know by doing reverse engineering. but office don't have symbols(public symbols) which gives too much pain and too hard for tracing or investigating .

i have done some RE activity via windbg by putting breakpoint and analysing each function and done some stack analysis.so looked into RTF specification and relying on some structure will be loaded into memory while debugging in Windbg. but lost everywhere..... And time consuming.

Even i ran Dynamorio, hoping for getting some results. but again failed....

Winafl Compatibility: As per winafl, i need to find a function which is taking some inputs and doing some interesting stuffs like parsing in my case.

but in my case it is way too difficult to get due to lack of symbols...

and i m asking, is it possible to doing code coverage and instrumentation fuzzing via winafl...

And what are the best possible and easy way to do RE activity on symbol less software like in my case?

so asking if anybody has any experience.....