Here is Hovind’s argument in a nutshell:
1) If you don’t know everything, you can’t be sure of anything
2) God knows everything and tells me things
3) Therefore all true knowledge comes from God.
The kid’s response cuts through his second and third point and just re-iterates the first broken assumption:
1)If you can’t know anything without knowing everything, how do you know God exists
And what’s Eric’s response? Rolling up his sleeves and basically dodging the question to avoid answering it, belittling the kid for not being very old (making himself look even more pathetic), and shuffling around hoping this embarrassing moment will soon be over. The lesson here folks is creationists can be brought down easily. You just need to call them out on their dumb shit and watch them squirm.