A great example to illustrate my point. Those verses are not remotely 'clear', let alone 'proof' of anything, unless your interpretation is determined in advance.
What do they actually say (I'll grant that is in translation)?;
So where's the reflected light from the sun (a.k.a 'lamp') bit? Where's the "not of its own" bit? Simply, it just isn't there.. unless you are desperate to see it. Why doesn't it say "the moon reflecting the light of the sun" or words to that effect - that I would have found rather more interesting.
Why was it not called "another lamp"? Because the sun is much brighter (bright = 'lamp', less bright= 'light')? Artistic style? ('placed therein a lamp and a lamp'?, 'placed therein two lamps'?) Who knows? But that's no excuse for reading in what simply isn't there. It's exactly the same with all the 'scientific proofs' regarding the Qur'an; I've looked at a couple in other threads.
To answer your precise question, my interpretation is that "He placed two lights in the sky". Maybe the use of "lamp" distinguishes the two - the sun and moon are clearly not identical - but no more. Sorry, but as I said this stuff convinces nobody who isn't already convinced.
There really isn't much point in bringing the Bible into it if you are addressing atheists, or at least non-theists! I could pick up just about any volume of my shelves and there wouldn't be any mathematical contradictions in that either!