I think it was more of a case of wanting to plant the remains were it could be investigated easily. Off the coast, in US territorial waters and airspace so there is no question, in a controlled area with no one under it to get hurt, and in shallow water so it could be retrieved.
Realistically, there are no unfriendlies that could have joined the party. Were was such an unfriendly going to come from? What was such an unfreindly going to do, watch?
T!