There's no 100% sure way to say where it originated. Fact is, is that the earliest accounts of homosexuality and pedophilia were in white societies.
So?
Is it that unreasonable to believe that:
1. Written african histories/traditions (if there were any) omitted any allusion to it because they didn't approve of it (as most societies didn't)?
2. Written african histories/traditions (if there are any) have been lost to history?
The tolerance of homosexuality is not the same as pedophilia. Don't equate the two again.
The tolerance of homosexuality in a society says NOTHING about whether or not society looked down upon it, or if its members engaged in it.
By this notion, simply because being gay is illegal in some countries, that means theres no gays.
That doesn't make any goddamn sense.