The atheist denial of purpose isn't a denial of secular or human purposes. It's a denial that God has a purpose for us. So he's set up a straw man that's easily knocked down.
The typical atheist claim that there are no miracles isn't that science somehow makes miracles impossible, as the author [trivially] points out, since miracles are by definition things which defy scientific understanding, such a thing is by definition -- and quite trivially -- impossible. Atheists are not stupid [any more than any other cross section of the population] and they don't make arguments on the basis of logical contradictions. The atheist claim is that there are no miracles happening now. And that is an argument that Christian [or any other religion's] Apologists must answer. This article bypasses an important question by attributing something to atheists that they don't claim.
Finally, 11 is simply wrong. The quantum vacuum is NOT a sea of energy. It is NOTHING. And he should not be trying to make the argument in the way he does, because his breathtaking lack of knowledge about physics makes him look silly. [Although to be fair to the author, a lot of "popular" books about physics describe the vacuum this way. These descriptions, like the author's are just plain wrong.]
The argument is about contingent versus Necessary Reality. God is the only Necessary Reality. All other things, material or otherwise, including the laws of physics and metaphysics are contingent. The metaphysics of God's Mind precede all contingent realities. The quantum mechanical law that a vacuum in the material world necessarily causes creation ex nihilo is a fact. That such a law exists is a contingent reality which depends on a Necessary One. The author's discussion confuses laws with their effects and really does not make any sense.
Hawking's attempt to argue away God fails because even if the extant laws require outcomes [as Hawking correctly observes] that doesn't explain where the laws came from to begin with. It is an article of Hawking's atheistic faith that the laws themselves are the Necessary Reality; and that takes us back to atheism being fundamentally about faith, not science.
If God doesn’t exist, then there is no evidence of his existence.
If God does exist, then everything is evidence of his existence.