“There is no headmaster to be notified if I kill you” was not said in Parseltongue, I think, so MM is presumably keyed into the Hogwarts wards at Headmaster level & may know Harry’s gone missing.
UPDATE: Hmm, there may be a different reason that sentence was not said in snakespeech—namely, the “I could kill you” part.
“I could kill you this instant, for there is no longer a Headmaster of Hogwarts to be informed of it. Doubt me all you wish, but remember that.”
“There is no headmaster to be notified if I kill you” was not said in Parseltongue, I think, so MM is presumably keyed into the Hogwarts wards at Headmaster level & may know Harry’s gone missing.
UPDATE: Hmm, there may be a different reason that sentence was not said in snakespeech—namely, the “I could kill you” part.