A Hercule Poirot Amuse-Bouche: The Disappearance of Mr. Davenheim by Agatha Christie

This week's pleasing Poirot puzzle is noteworthy for a few reasons:
1) it features Agatha Christie's recitation of the different ways a
person might disappear, written five years *before* her own
disappearance; 2) the Suchet adaptation features a bit of
delightful wordplay involving a parrot; and 3) that same parrot
leads to perhaps the greatest Hastings putdown ever recorded. Poor,
poor Hastings....