While I appreciate the attention drawn to my academic article and my translations of Alevi hymns, I should like to make some remarks on the question and perhaps provide some answers.
First of all, the source noted does not contain "a hymn" but an entire liturgy with multiple texts. Let us not diminish the achievement, such as it is, of putting a whole collection of Turkish Alevi hymns into English rhymed verse that fits the original Turkish melodies.
The second issue is in the identification of the articles. The entire academic article is entitled "Ritual Change in a Turkish Alevi Village." The website linked above refers to the last section of the article, which it quotes, and which bears the section title "Rites of Sacrifice in a Turkish Alevi Village." The latter is thus a section of the original and far more extensive complete article. Perhaps there is some ambiguity there, but I suspect an examination of both sources would clear that up.
Both sources clearly identify the author accurately as Thomas McElwain. But the questioner finds reference to "Ali Haydar" somehow a justification for "chasing whispers and shadows." There is nothing sinister, strange, occult, or dishonest involved. It was simply that while working in the village of Sarilar, people jokingly complained that Thomas is a word too difficult to pronounce, and so I was given a local nickname that has stuck among Muslim friends and occasionally appears here and there. I felt it at the time to be a gesture of friendship, acceptance, and in some measure even affection. It takes the internet to replace such things with suspicion and possibly even hostility. Let's go back to the original intent and atmosphere. Thomas McElwain remains my birth name and official name. Some people, on converting to Islam, change their names officially. That could have been the case here, but it is not. Such a religious name change ought to have been the first explanation to come to mind, rather than something nefarious, a pseudonym, or an attempt at co-opting a "false persona."
This is a site that deals primarily with literature. If the explanation of religious conversion does not immediately come to mind among those interested in literature, it does come to mind when the term "nom de plume" was replaced by "false persona." I should think that might have entered the speculation long before the thought of someone clandestinely trying to come across as native where he was not. But it was not a matter of anything so pretentious as a nom de plume either.
Let me thank, however, the questioner for flattering me with the implication that my spoken Turkish was of such excellence, that I might have been able to maintain the "false persona" of being Turkish in a Turkish village. My written work might have excused such an impression, but experience will show that there is a great difference between being able to work on paper and speak a language with the fluency required to pass oneself off as a native. I have been mistaken in France for being French, in Spain for being a Spaniard, in Finland for being a Finn, but never in Turkey for being Turkish. Wait! I am trying to be so accurate that I can escape the darts of the discourteous, no doubt a futile hope. My daughter and I were in fact mistaken for being Turkish in a shop in Istanbul, when we were amusing ourselves by speaking Turkish together at a moment when it rose to slightly more fluency after being in the country for several weeks. But it was only for a moment. There was no attempt to maintain a "false persona" or "create whispers and shadows."