Why does God exist?

[Undeceived]

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According to our universal laws, everything needs a cause--including the universe. Therefore a force outside of our universal laws must be responsible. Why do you disagree with this?

You're committing a quantifier-shift fallacy.

I am speaking on the molecular level. The first atoms don't simply exist, they began to exist. Scientists admit to a burst of positive energy at the "Big Bang." This positive energy needs a catalyst in order to split from the negative energy. So I reach the conclusion "all things have one cause" on reasoning separate from the single premise "all observed things have a cause." It is quite possible for both ends of
[For every A, there is a B, such that C. Therefore, there is a B, such that for every A, C ]
to be true. It is only fallacious when you use the whole as your deduction.
To be clearer, my argument: According to observation and testing of our universal laws, all transference of energy has had a cause. Also, all causes create a transference of energy. No cause has been observed without a transference and no transference has been observed to be without cause. Therefore, all transference of energy necessitates a cause. Hence, any production of atoms using energy also needs a cause. Therefore the universe could not have begun without a cause. I conclude we need either a catalyst not bound to this law of causation (non-natural) or one outside of the universe's closed system (also technically non-natural).
Why do you disagree?

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Universal means everything, how can there be a force outside of everything? In fact "outside everything" is meaningless.

Universal means everything in the universe. Why can there not be something outside of the universe (exo-universal)? Our laws seems to require that there be, lest we fall into paradox.