Fortunado's Dramatic Death; for real?

“‘FOR THE LOVE OF GOD, MONTRESOR!’” cries the ill-fated Fortunado as he dies at the hands of Montresor, the narrator—or so Montresor would like his readers to believe. In “The Cask of Amontillado” by Edgar Allan Poe, Montresor tells a dramatic recount of a murder he claims to have committed fifty years ago.
While some of Montresor’s account of what might have happened with himself and Fortunato may be accurate, he is overall not a trustworthy narrator. In the very first line of the short story, Montresor tells the reader that he has a negative bias towards the unfortunate Fortunado. “The thousand injuries of Fortunado I had borne as best I could, but when he ventured upon insult, I vowed revenge. You, who so well know the nature of my soul, will not suppose, however, that I gave utterance to a threat.” His opening statement to the short story clearly implies that he had a prior malicious will toward Fortunado, so any account that Montresor gives of Fortunado’s character cannot be taken as something that is certainly true. The reader can tell that Fortunado’s character will be painted unfairly by Montresor. Montresor indeed depicts Fortunado as a rather dull, weak drunkard. Furthermore, from the same opening statement, he shows us that he can be deceptive; he conceals his thoughts towards revenge from Fortunado, so from the very beginning we can tell that he might change or embellish the truth in his story; for what we know, he might have made up the entire tale.
The conclusion of his story also gives reason to question the credibility of Montresor’s tale. “Against the new masonry I reerected the old rampart of bones. For half of a century no mortal has disturbed them.” He claims that all of this happened five decades ago; we can be almost certain that some of the details of this night have become clouded in this crazy man’s memory with the passage of time.