Thank you for your explanation, Nanal.
Here are a few general points.
1) There are relatively few existing documents about Hamshen's history. Maybe some more can be found in the future but at the end end there will not be many documents. One of the most important reasons for this is that it was a hard to reach area and a relatively unimportant place, so the Ottoman, Armenian and foreign documents aren't many. For example, there has been no document telling us exactly which year the conversions began or who were among the first converted in which village. There are some documents showing some Christian churches and Christians still existing in some Hamshen villages in the 18th century and there are plenty of circumstantial evidence like mosque building, appearance of Muslim tombs, exodus of those Hamshen people who did not want to convert to Islam etc. starting late 17th century. These all agree with each other well. If this data didn't fit with each other well, I could say there are doubts about the general period. But is is not the case. As I said, the general picture is certain but we don't know the details. For example, the same can be said about the conversion of the Laz -- the general period is known but no one knows exactly which year it began. Also, we don't know most details about the Greeks of Trabzon or the Georgians of Artvin converting. History cannot record everything.
2) The most informative and definitive book about Hamshen in English is "The Hemshin". You must have seen it mentioned in this Forum. Again, this book cannot give you all the answers you hope to see but it has much more information than found elsewhere. So it will not exactly give you something as definitive like a blood test answers to show it to those Hemshinli who don't want to admit Armenian origins. But it will give you much more information to anybody than ever before. That brings me to the next point.
3) You and some Hemshinli who want to preserve your culture are open to find out about your past. The Hemshinli who don't want to admit Armenian origins have political reasons rather than cultural ones, so that's why they also say they came from Central Asia. Whatever amount of documentation probably will not make any difference to them. For example, it is common knowledge that many old age people when they were children in Hamshen had heard from their grandparents that their ancestors were Armenians. The "no sayers" know this but they call the old people idiots or illiterate to suppress such oral traditions. The neighbors of the Hemshinli call them Armenian behind their backs. Are they idiots too? The Christians of Hamshen who left the area have oral traditions saying that they had left behind relatives in Hamshen. There are clan (sulale) names that are the same between the both sides. Of course, the average Hemshinli looks like an Armenian, not a Central Asian. So, any person without an agenda would come to only one conclusion. But everybody knows that those people and many others from other ethnic groups in Turkey want to believe that they came from Central Asia.
At the end, everybody is free to declare they believe in a certain thing even though they really don't believe in it. And nobody can force anyone to be rational. However, no one in the world takes seriously the fake histories that have been forced on millions of people for whatever political reason.