Well, whether or not it came from old Witty, I still believe that it is fake.
If he sold you this dagger 5 years ago, I sincerely believe that it could have been an honest mistake.
There are actually only a handfull of experts that I would really trust for authenticating Rohm blades, Craig being one of them but it would have to be a physical inspection.
The best person for the job though would be Gailen David but I think that he no longers does it.

Read the following thread.
http://daggers.infopop.cc/eve/forums/a/tpc/f/477091573/m/6710087993

Everyone thought that the E.Pack was a complete fake.
This faked E.Pack Rohm dagger is even listed in Steven's reference book on "Reproductions" and has the same identical flaws as the one pictured.
Guess where this dagger came from ?
Wink