If God can't do any possible thing, then how could God be omnipotent? The definition of omnipotent is literally, "having unlimited power; able to do anything." If God does not have unlimited power, and God does not have the ability to do anything, then God is not God.
Nonsense, if we all have a sense of what God is like, why did the native americans do rain dances rather than praying? Why did the egyptians build elaborate pyramids and temples, rather than churches and synagogues? Why did Christ need to even come in the first place to save us from our sins, if we "have a sense of what God is like prior to revelation, then we wouldn't NEED redemption through Jesus Christ, because we would already have a "sense" of what to do.
You didn't disprove anything, you just put forth a hypothetical that can't be truly answered by us (because we're not God), and then you act as if this is "proof" of God's fallibility, when in reality this is just YOUR falible, human interpretation of a truly omnipotent, indescribably powerful God that you cannot ever fully understand. It literally says in the bible, Matthew 19:26, "But Jesus beheld them, and said unto them, With men this is impossible; but with God all things are possible.". So was Jesus lying here?
Luke 1:37, "For nothing will be impossible with God.".
Job 42:2, "I know that You can do all things, And that no purpose of Yours can be thwarted."
So now I have to ask, do you believe in the God of the Bible, or some Pagan nonsense?
Being "closer" to the truth does not matter, they were still wrong, and if it were not for revelation, they would continue to be wrong. God is the father, the son, and the holy spirit, everything else is heresy.
But if God had not revealed himself to them, they would have never stumbled upon Christianity, which is the only true religion. All other forms of monotheism are false.
It's pretty obvious now that you're not truly a Christian.