“whether apprehended or not” is a kind of hedging the bet against arguments that your personal religious feelings are felt by everyone, and so has no actual theistic, much less Christian content.
The problem with using that turn of phrase is that you can always just fall back on that excuse. You can concede that someone else, of a different religion, or even a nonbeliever, can get the same feeling and experience that you do, but just rationalize that they’re somehow not properly “apprehending” the experience as a “witness of the Holy Spirit” that confirms the truth of Christianity.
But that is all that is, a rationalization you’ve internalized, to regurgitate for this exact situation. Where evidence from the real world(that other people have similarly powerful religious experiences) should cause you to think that perhaps yours isn’t from “the Holy Spirit” after all, you have been provided this fall-back excuse.
In a way this is similar to what conspiracy theorists and Flat-Earthers do when you provide them a satellite picture of Earth, depicting a sphere in space. They then automatically go to their rationalization that the picture is fake, and has been photoshopped.
You can always just rationalize in the same way that Craig does, that “I merely happen to be in some historically contingent circumstance, so even though now the evidence is against me, I can fall back on my internal feeling of the Holy Spirit and remain a believer even if the evidence remains against me for the rest of my life, or until such a time that new evidence that turns the situation around is found again”.
Once you allow yourself to be persuaded to adopt these fits-all rules that can always be invoked in ad-hoc manner to dismiss and explain away any imaginable contradictory evidence, then you have made it impossible for yourself to discover if you are actually wrong.
To adopt Craig’s stance here is to seal yourself off emotionally and intellectually from the possibility that your position is wrong. A sort of epistemological valve that will allow you to enter into the Christian faith(or whatever belief it is), but from which you can’t escape again because now this internal rule that becomes active on the inside won’t allow you to conclude that you are mistaken.
That’s a bug, not a feature. An epistemology that allows you to move into such a sealed state of mind is patently irrational.