Let me try this once again.
The measurement of the CMB in the 1960s established that the universe is expanding and thus there was a beginning of real space and real time in the physical realm. It was celebrated as a confirmation of this phrase of this verse:
It was not merely a vacuum, it was void. There were no boundaries of any kind. All that is before the beginning is singular, i.e. God.
This means that in order for there to be a beginning there had to be an uncaused cause of it. Consider the void, only God could make a beginning ex nihilo.
As you say, the beginning itself is an event, that means that God created real time and real space in the beginning.
The spiritual understanding I have of Genesis 1-4 is that it is a summary of God creating both the spiritual realm and the physical realm. Consider also Colossians 1. God creates both spiritual and physical realms and beings consisting of both form and power. Therefore, it is quite apparent that God created geometry (space/time continuum of unknown dimensions) which applies to both spiritual and physical realms, in the beginning:
It doesnt matter what cosmology a person holds big bang, cyclic, ekpyrotic, multi-verse, etc - because every single one of them must have pre-existing geometry (space/time) in order to have physical causation. They cannot obviate God. Period.
Back in the day when man was able to believe in a steady state universe, he was able to obviate God and laugh at the Godhead as the consequence of an overactive imagination. Why? Because in a steady state universe, God must exist in space and time!
It was one of the many ways man anthropomorphized God.
Continuing on the issues at hand ... how one looks at the question of which came first in the physical realm energy/matter or geometry depends a lot on his understanding of the quantum world.
On the one hand are those who lean to high energy particle physics. These have a tendency to consider the particles such as photons as real and local (even though they often recognize that is not established.) IOW, science has observed non-locality that measuring one of two entangled photons will determine the other regardless of spatial separation, whether 11 kilometers, across the solar system, galaxy, universe. Also, ordinary matter (the Higgs boson) has not yet been observed or created by either Fermilab or CERN and thus there are new theories, e.g. that matter in four dimensions may be a shadow of momentum components in a fifth dimension.
But I digress
The other side (obviously I am one) leans to quantum field theory. A field is defined as existing in all points of space/time, the geometry of the physical realm. Thus phenomena such as non-locality and quantum superposition and matter become an issue of the geometry itself.
Technically as to how the physicists do science it doesnt matter much whether they use quantum mechanics or quantum field theory but it does matter how one visualizes physical reality.
The former see the uncaused cause causing energy (e.g. big bang) which as in the case of matter/anti-matter colliding in a burst of gamma radiation, expanded the geometry of the energy. Thus, in that view space/time is created by the energy/matter, i.e. it inflates exponentially.
On my side of the aisle, God creates a speck of geometry (space and time of unknown dimensions) which causes vibration (string theory) and gives rise to quantum fields and therefore the matter/anti-matter collisions which result in a burst of gamma radiation, inflating the geometry exponentially.
Or the "chicken and egg" problem of energy/matter v geometry could simply be that God created both simultaneously...
I can't get by the question .. expanding into WHAT?..
Is the Universe a balloon?..
I don't necessarily disagree with you on sicence/math either. I just don't embrace current theories witht he same finality as some do because I have seen theories change in my own liftime and I have no doubt they will change again, even radically.
Again, if God is not logical, in the human sense, then the truth may be completely irrational. For, as Pascal posits that we can never really know God, God's ways may turn out to be be a real surprise, and quite unreachanble by any science.
For the sake of brevity, I understand the CMB issue and the steady-state defunct theory. I am only looking at the "void" you are describing and asking you if such "void" is created or uncreated?
For, if there was nothing but God, and only God pre-existed everything and all, that would include the "void." But the "void" istelf cannot be "void" because it was from its beginning filled with God if not by matter.
So, if God pre-existed everything, which must include the "void," then the "void" itself must be a creation, a receptacle of the Creation to come, and its act of creation is an event in absence of time, whose existence appears without the presence of matter/energy because it's a void.
This reminds me of another defunct physical postulate, namely the "ether," which supposedly filled the outer space.