Yeah, that's the problem. Extraordinary claims and all that...
Having his imagination fired by Oumuamua and to then go looking for potential interstellar material on Earth is, I think, good science. But he has yet to prove that the material he's recovered is not of terrestrial origin, let alone it being interstellar material. And to then make the extraordinary claim that some tiny balls of iron are the remnants of a space ship. The analysis of the material he presents had better be extraordinary evidence.