I think you might be in error with this statement. Simply Googling "homosexuality in tribal culture" provided me with all sorts of links to information about tribal cultures around the world who recognized and accepted homosexual members within their tribes.
This includes, but is not limited to:
Native American "Two-Spirit" individuals, with only the Comanche and most clans of the Apache NOT recognizing this class of person;
https://en.wikipedia.org/wiki/Two-Spirit
The Etoro People of New Guinea;
https://en.wikipedia.org/wiki/Etoro_people
A link to 21 varieties of traditional African homosexuality;
21 varieties of traditional African homosexuality | 76 CRIMES
The list of links goes on for page after page concerning all sorts of cultures from Europe to Asia and around the world. Same sex individuals appear, accepted or not. I believe if you Google or Bing any specific ancient cultural group you will be more likely than not to find references to homosexuality in their cultures.
Now the rest of your post is personal speculation and opinion, and everyone is entitled to that. But claiming an analysis of tribal cultures will show a majority were unaware of or lack understanding of homosexuality is simply untrue.