I beg to differ.
I came across this wonderful argument a while back that argues pretty decisively that if god existed, then he would indeed be the sole cause of natural disasters. The argument goes like this:
(1) God (an omnipotent, omniscience, omni-benevolent being) exists.
(2) Natural evil exists.
(3) God is the creator and designer of the physical universe, including the laws that govern it.
(4) Natural disasters, and the evil they cause, are a direct byproduct of the laws that govern our universe.
I don't think Craig would deny premises 1-3, although he might challenge premise 2. In the Q&A he wrote:
For what is bad about natural evils is not simply the occurrence of certain natural events themselves. There is nothing evil, for example, about one continental plate’s slipping under another, nor about the earth’s trembling as a result. Such natural events are themselves ethically neutral; morality doesn’t apply to rocks and rain and wind. Rather if there is something bad about such events, it’s that human beings get caught in them.
I would agree but go a step further that it is not just people getting caught up in natural disasters that make them evil under theism, but any conscious animal that can suffer as well. That would mean that the millions of years of non-human suffering as the result of natural disasters would be evil under a theistic worldview. So given Craig's response above, I don't think he would object to premise 2.
Premise 4 is actually what Craig would seem to object to, and his first option out of god being responsible for natural evil is an appeal to quantum indeterminacy. He writes:
...if quantum indeterminacy is ontic, God could not cause an earthquake to occur at a specific time and place just by setting up the natural laws and initial conditions of the universe. If an earthquake does occur, it is only because God did not intervene to stop it. That is to say, He permitted it. Problem solved.
But god would have designed the physical universe, including the laws that govern it and would have chosen to make the universe inherently random at a fundamental level. Furthermore, god's foreknowledge would allow him to know exactly when every natural disaster would occur, even with quantum indeterminacy. I'm simply not buying the case that god creates a universe and then is shocked at how much natural suffering it causes. And Craig doesn't seem to be making that case either. He seems to be trying to argue that if quantum indeterminacy is real, then god does not directly cause every natural disaster. The beauty of the above argument I'm defending is that is god would still ultimately be responsible for natural disasters, at least indirectly, because he is still the one calling the shots on how the universe will operate and he has foreknowledge. So the problem is not solved.