God’s Creation of Time

Dear Dr. Craig,
One common objection (e.g., Grünbaum) to your view of the universe's beginning is that the moment of creation cannot be "before" the universe's actualization, since that already presupposes the time of the universe. In response, you've proposed that perhaps the moment of creation of the universe was simultaneous with the universe's beginning, thus no longer needing a "before".
But our notion of what it is for an event to be simultaneous with another event can only make sense within an already existing space and time (irrespective of whether simultaneity is taken here as absolute or relative).
So to talk of space and time itself as being in a simultaneous relationship with a cause or moment of creation (as if space and time is a spatio-temporal thing or event itself) seems unintelligible. Our notion of simultaneity, or coincidence, and even our notion of what it is for something to be an event, surely can only make sense within an already existing space and time.
Lastly, if one claims that perhaps the property of simultaneity itself also begins at the SAME TIME (or "simultaneous") with the universe's beginning and its cause, then one would seem require a second-order simultaneity, which again seems unintelligible.
How would you address this difficulty?

Click HERE to read Dr. Craig's answer