Re: V'Ger origins: Borg or not?
Going strictly by Canon won't help here. Roddenberry himself once said  the machine planet was the Borg homeworld, he could be joking or not, ymmv.
I do recall him saying something about this (though I don't remember in what publication as there was no internet as we know it then). Even at that time, it was clear he was speaking somewhat in jest, and it was not a serious thought.
Dr. Howard, Dr. Fine, Dr. Howard: For duty and humanity! --Men in Black (1934)