I will prove to you that God exists

[Sheldon]

If that is Stenger's argument, then he isn't using theology. He's just using logic.

I am open to the possibility of the existence of a creator; I don't think there are any universe origin stories that are intuitive to me.

But I can, with certainty, disqualify any number of possible deities and religions as being true. Even the most devout religious person does this as well, seeing as they have to accept one god/religion and reject all others. And a God who claims to be concerned with my wellbeing and my future prospects, but does nothing to address those concerns, is pretty easy to dismiss. Heck, any God that created our universe and our world out of a desire to have anything to do with us, and then never ever shows up, can be tossed on that pile as well. There are a long list of ways in which pretty much every God that people worship isn't real.

"God has to exist, check out these proofs" is simply unconvincing and unsatisfying. Explain how the one YOU believe in is actually real.

I believe the universe was intentionally caused to exist by a being capable of doing so. I 'm a philosophical theist.

Philosophical theism is the belief that the Supreme Being exists (or must exist) independent of the teaching or revelation of any particular religion.[1] It represents belief in God entirely without doctrine, except for that which can be discerned by reason and the contemplation of natural laws.

The problem is your reasoning thus far has been demonstrably flawed and often fallacious. It misunderstands / misrepresent scientific terms like fine tuning, which is a metaphor to describe natural characteristics of the universe, by falsely implying it represents scientific evidence of a supernatural cause to the universe, and you have used fallacious arguments, and tacked on large assumptions, without even the pretence of any objective evidence. 

Our existence could be the result of a scientist in another universe.

Could it? How would you even start to demonstrate this is possible? It seems like a sweeping, unevidenced,  and unfalsifiable assertion to me.