No, I think Anon has been cleared because of the statement in the NP, "Ron locked anon in the Room of Requirement...". Obviously, Ron wouldn't block himself, so anon isn't Ron. Ron probably wouldn't block anon, if anon was Harry, as Harry carries out the NK. And he couldn't have blocked anon as Hermione, as Hermione was killed by Snape. [Does that make sense to anybody besides me? ] But I think anon has been cleared.
edit: I went back and read the OP. OOA says that NK comes before block, so Ron couldn't have blocked Harry anyways, because the night kill would've come first.