God is not a disprovable concept. Regardless, I’m not sure what His relevance really is, ultimately, in this context or any other. An eternal universe/multiverse would, by definition, have no creator. Likewise, an eternal God would have no creator. So, in this sense, there is no difference between them. As for morality or an ultimate code of conduct delivered to us from on high, if God created this code for a reason, then it is the reasons we should be focused on and not the fact they came from God. In other words, the reasons are the ultimate source of our morality and not a deity. If God had no reasons in mind, He was merely acting arbitrarily, or perhaps His emotions got the better of Him. That second option would render Him imperfect, however, which is not acceptable from a monotheistic perspective. God ultimately doesn’t explain anything.