Will Worf go to Sto Vo Kor? Well, only if it exists. And its existence would appear to depend chiefly on whether Worf believes in it. If he does, I'd think the odds are that he would also believe he's eligible to enter - and that's all it would take.
Of course, it's all merely taking place in the dark, oxygen-starved corners of Worf's dying mind before the final nothingness sets in. But while Worf is a great worrier in life, I don't think he would wallow in self-doubt at the very moment of his death. He'd make damn sure he was in a deep purple haze of glory when the end came, no matter what its exact form.