The Hunza of Pakistan and ancient Proto-Balkan-Caucasian peoples

In the past two years I had been reading many theories about the existence of a proposed family of Dene'-Caucasian languages.
Many theories of Proto-Caucasian (Caucasian as in people of the Caucasus see my other post) peoples and languages being spoken across Europe prior to the Indo-European migration which is believed to have occurred sometime during the fourth millennium BC onwards.

Prior to this time period in human history, little has been known about Europe until new research emerged about the possibility of Proto-Caucasian languages being amongst the many diverse language families spoken in the region of which may have been survived by Basque.

Many recent hypothesis suggest Proto-Caucasians languages and peoples populating areas of Europe. Certain linguistic theories have also linked the Burushaski language of hypothetical Caucasian families that also include Basque.
These hypothesis, though not proven lead me to a theory of my own. Despite lack of genetic evidence to support it and being doubtful of genetic results since most DNA tests on the Hunza populations seem show them to be related to the rest of Pakistan. I theorized that for the Basque and other extinct Caucasian languages to be spoken in Europe, a mass set of migrations must have taken place.

Thousands of years before the rise of the ancient Indo-Europeans, Proto-Caucasian tribes left their original homeland and moved westward and possibly southward since there are theories that the Sumerian language may be related to modern Caucasian languages.

But amongst these Proto-Caucasian migrations, a tribe or small set of tribes somehow ended up moving eastward. There are many cases of small populations migrating in opposite directions of the larger family, such as the case of the Tocharians who are said to be a Proto-Celtic tribe ending up in the Chinese desert instead of going along with the rest of the Indo-European migration.

If an established link is found between Basque and modern Caucasian languages as well as Burushaski and Ibero-Caucasian, then my theory is that the Hunza were a lost ancient Proto-Caucasian tribe that settled in Pakistan many hundred perhaps thousands of years prior to Indo-European domination in most of Eurasia.

Perhaps the Hunza are not descendants of these people as per most of the genetic evidence, but the language they speak may have come through a Proto-Balkan-Caucasian tribe that settled in Pakistan.

The Hunza are amongst the fairest people in Pakistan and bear a closer physical resemblance to Caucasian and European populations than to most Pakistani populations despite being closely related genetically; hence they might not be related to the people of the Caucasus genetically, but rather a people who inherited a Proto-Caucasian language due to nomadic settlements.

Or the alternate scenario could be that the Proto-Caucasians are the ancestors of the Hunza and absorbed outside genes as race mixing occurred.

Random migrations in ancient times may have led these Caucasians to enter the Indus Valley many thousands of years ago.
Only further research will reveal what the world was like prior to massive expansions and dominance of the speakers of many language families today, primarily Altaic and Indo-European.