The Objective Moral Values Argument AGAINST The Existence Of God

[Edwardo Piet]

I have come up with a counterargument for this standard objective moral values argument for the existence of God that goes as follows:

Premise 1: Objective moral values exist.
Premise 2: If God does not exist then objective moral values do not exist.
Conclusion: Therefore God exists.

My argument against that argument is as follows:

Premise 1: The only rational reason to believe that God exists is to rationally believe that both objective moral values do exist and that God cannot exist without those objective moral values.
Premise 2: If the existence of objective moral values is the only rational reason to believe in God then without that reason it would be more parsimonious to not believe in God.
Premise 3. If all other relevant reasons are equal then it is more rational to be parsimonious.
Premise 4: But because there is no other rational reason to believe in God besides objective moral values then without that reason all relevant reasons are indeed equal.
Premise 5: It is more parsimonious to believe in objective moral values without the existence of God.
Conclusion 1: It is more rational to believe in objective moral values without the existence of God if the existence of God is not required for objective values to exist.
Premise 6: There is simply no reason to believe that the existence of objective moral values require God's existence.
Premise 7: Objective moral values do exist.
Final conclusion: It is more rational to not believe in God than to believe in God.

Note: I don't actually believe that objective moral values exist, as most atheists don't, but as far as I'm concerned this is a smackdown against the idea that if objective moral values exist then it's more rational to believe in God than disbelieve in God.

Also note that this argument relies on the premise that there are no other good reasons to believe in God... but my point here is that anytime any theist brings up the argument from objective morality as a way to prove God's existence it is now clear that that argument of theirs is absolutely useless unless they also have other arguments to support God's existence.

EDIT: I don't actually need Premise 2 at all but premise 2 makes the argument a lot clearer and more explicit, I think.