We learned that he had actually been buried where he was found and not washed down from some other area.
That means that there must be others here. You are correct that we still don't know his ancestry for sure.
Yes, you are correct.
Chatters speculated that he may have fallen and drowned in the river and washed about after his death. There will be hell to pay when the scientists propose to remove all the derbis put over the grave site by the Corps Of Engineers.