Involving the police for something like that is not a threat to your safety in a civilised country. It is, indeed, the best course of action in any country with a functioning police force.
Well, a functioning police force wouldn't mind if you reach to online communities and paleontologists to verify that those remains are human before reaching to police to file a report, I'd assume.
And so, if the law force action could have serious consequences, then the tiles would be better left untouched, no paperwork needed. And if it couldn't, then it's okay not to file paperwork first.
