I have had people claim, on the basis of some caulk marks indicating it was in the inventory of a smaller museum, that the item is "legit" because it had been in a museum collection. It only takes one mediocre curator to buy junk. Often, when they do, they try to make a claim that it is legit, and try to re-coop their $$$ by finding another sucker.
30 or so years ago, one guy in his early 20s fooled, basically, the entire higher up of the Morman Church (LDS). I think his name was Hofmann, he claimed he had found serveral rare documents, which could be traced back to a church founder. As I recall he was taking new paper, forging handwriting of legit people, and spraying it with ammonia. The docuents were reviewed by experts who deemed them legit.
Eventually he was exposed - and then it turned into a real mess, as I recall he tried to kill one of the people who exposed him.
I know I am off point on the OP. Yet, I am reiterating Caveot Emptor. I dont care who says what, at the end of the day you have to make your own decision and live with it.