I have displayed Fossil Walrus Ivory with African Elephant and even experts can't tell the difference. They told me that a DNA test is the only positive way to confirm the material.
Who is going to do that? But, it is your responsibility to prove that it isn't African or Asian Elephant Ivory (that has been totally banned).
Isn't one of the basic premises of our legal system that you are innocent or truthful until proven guilty or deceptive?