No, but those tests and observations have led us to the Big Bang. And as theories develop and instruments get better, we’ll have even more evidence. And if the evidence and theory points to something else, that something else will take the place of the Big Bang.
But anyway, you are asking for mutually exclusive things, first you want to say that “God is outside observation” then you want to say “Traces of God is observable.”
You can’t have it both ways. If you want God to be a part of science, if He doesn’t exist following the rules of science, then you would have to admit God doesn’t exist.
Oh? These are mutually exclusive now? I guess we can dismiss all evidence of subatomic particles now, since they are outside of our ability to observe directly--never mind that we can see their effects.
Funny thing: I've never observed a reptile evolve into a bird. Have you? I never saw the Egyptians build the Great Pyramid? Did you? Have you ever replicated either of these events in the laboratory?
Nope. Yet you still believe in ancient Egyptians, despite the fact that you have never seen one.
I see no more reason that the IDers should have to bear the burden of proof than those who claim that the pyramids were built by human beings should have to defend their belief against the proposition that they're just oddly symmetrical natural mountains.