In the void of the beginning there is no space, no time, no energy/matter, no physical laws, no physical constants, no mathematics, no logic, no universals, no forms, no autonomy, no qualia, no physical causation. There is no physical causation in the void - the first cause must be uncaused and the only candidate for uncaused cause is God.
The sort of void you describe is indistinguishable from a perfect unity, and so would be indistinguishable from what you're calling 'God'. You're running up against the old problem of coincidentia oppositorum here, and Hegel's "the night in which all cows are black". Care is warranted!
Indeed, the Hebrew term for God as Creator (in the void) is Ayn Sof which means "no thing" - One without end from which all being emerges and into which all being dissolves.
It seems like whenever we get into discussions of time - whether on science or religion threads - we end up with the issue of whether God is transcendent or immanent. God is both.