Yeah some will make an outward confession that Jesus is God, but is it a genuine confession by faith, that would be the question?
It's like the article Refreshed put up recently (if I am remembering correctly) that talked about all the people that make an outward confession of their belief in Jesus, but when you start digging a little deeper, turns out they really don't believe in the Jesus of the bible as evidenced by them admitting on further questioning that Jesus is not the only way to be saved, etc.
So just an outward confession is not a surefire test for us, it must be a genuine confession from genuine faith (which only God knows for certain). But if someone outright denies Jesus is God, then there's not anything more to question.