Scientists suck at philosophical argument. Seriously, they seem very handicapped by the inability to think outside of material terms.
Either Hawking's argument is woefully misrepresented or Hawking said something amazingly stupid.
If God is postulated as "the personality that created observed time-space" then protesting there was no time prior to that creation event fails to even recognize the question. Time-space is the essence of Nature. If it is created its creator would be above Nature - literally supernatural. What these scientists are doing is discounting the supernatural a priori. That's not scientific - because they have no direct observation, while asserting no observation is possible - that's just close mindedness.
They are free to suggest we cannot make observations outside of space-time but they betray a certain hypocrisy when they concurrently assert the supernatural cannot interact with our space-time (which religion labels as revelation). They are assigning attributes to things they say they are unable to test.
That's an act of faith. A thing they dismiss when it comes from others.
But, most strikingly of all, they want us to believe they have reasoned this inside their minds. What are their minds? Their brains, they will answer. But what is the brain? A collection of synapses formed of cells. And the cells? Proteins and other long-chain molecules held together and self replicating as matters of biochemical action and reaction. The molecules? Clusters of various atomic elements. What are atoms? Protons, neutrons, and electrons. And these subatomic particles? Expressions of quantum phenomenon that cannot even be wholly observed. In fact, they are barely described as particles or waves, but more as states from moment to moment. And these states are reduced to vibrations and perturbations in the very fabric of time-space itself.
They are saying ripples on the surface of the pond have become philosophers and scientists even though nothing in the nature of the pond or its animations comes close to suggesting such a state is possible. They simply assume it must have happened of its own accord because - lo and behold - here they are and anything else offends them, particularly suggesting someone else may have dipped their finger into the pond.