Baloney. That's circular reasoning to fulfill a narrow interpretation of scripture. David knew a messiah was coming, he didn't know His name or that he had to place his faith in a personal relationship with Jesus.
Are you saying a pygmie who has never heard of or encountered Jesus can still be saved?
That isn't exactly what I'm saying (I don't know one way or the other). I'm saying that, hypothetically, if he WAS saved... it would still be "through Jesus". Thus the verse "no man comes to the Father" does not imply that a particular formula for accepting Christ is the only way. YOU appear to have set the bar rather low with all of the other people who "believed in Jesus" though they would have been shocked to hear that they did.