I'm right there with you.
Four things that stick out:
1. It's Fenn himself claiming it was found (as it was just Fenn himself saying it was buried, with no proof and no witnesses), it wasn't the finder himself coming forward to the public.
2. Fenn said its "some" guy from the east who "is shy" Yet, Fenn indicates the guy contacted him to prove he found it. If you truly wanted to stay anonymous, contacting the original owner, is not the way to do it. The IRS will have no problem finding you now that you contacted Fenn (if your goal was to avoid the taxman, but Fenn claims its because he is "shy").
3. Fenn says the guy sent him a picture of the chest. Let us see the picture.
4. Since it's been found, why not just tell us where he had originally buried it?