God said, “Let there be a firmament in the midst of the waters, and let it separate between water and water..."
The firmament kept the water from the sky (rain) from meeting the waters of the earth. And that when it rains, that is God opening up the vault of the sky. The stars were believed to be like little bits of light on the firmament (in revelations they were depicted as falling down to Earth). Rather than a sky like our modern understanding, the world would be much more akin to a snow-globe.
Now back to my question, if that bit of cosmology was right, would it be evidence for the Bible?
There would certainly be arguments in favor of this,
Psalm 19:1, “The heavens [shamayim] tell out the glory of God, the vault of heaven [raqiya] reveals his handiwork.”
The complexity of the firmament certainly suggests a deity right? Well, not really. The reality is more complex and reality doesn't suggest such a thing and though there are no laws of physics which allow for a firmament as such, we would have to have hypothetically different laws of physics to account for this cosmology. Though, maybe with our actual laws of physics and this weird outcome might provide some evidence.
But, they predicted it right and there's no way they could have predicted that the whole world was under this dome sky-like thing, right? Well, that's not true either. First, looking at the sky might give one that impression (plane tangent to sky does seem to be a dome) and secondly the Greeks had that cosmology first. For example, in the Bible is says that the Earth is hung upon nothing. -- a comment to which many creationists pat themselves on the back over and over again. While at the same time ignoring everywhere it says (often right next to it) that the earth was fixed and unmoving.
A while back in a podcast, the Non-Prophets mentioned that it would be evidence for the Bible if there actually was a firmament, but I don't think it would count for the Bible at all. The fact that the idea that the sky is a firmament is dead wrong is an obvious mark against the Bible, but being correct isn't a mark for it either. Which oddly seems to veer off towards Hempel's paradox, noting that exceptions to rules disprove the rule, but that non-exceptions don't make the rule any more or less valid. Though, there's shades of gray concerning the idea of being wrong.
Even if we knew of nothing that discredited the cosmology, history, or understanding of the Bible it would provide absolutely no evidence in favor of the accuracy of the book. And really, that's the essence of science. You try to disprove something until you finally give up and use it for anything you need the idea for. If the rule holds for more things than the previous rule, well then use that rule instead.
The only thing the Bible could hope for would be accuracy and frankly it missed that boat. I think the accuracy of the Bible must have drowned in Noah's flood.