Go back and reread it. He said at least some convert that way. Ummm, no they don't. Also, acknowledging God exists is non-sequitor. Those who have not heard the gospel never had a bible in their hand, never had someone witness to them, does not wake up one day, look at the sky and think, "God sent His Son to live a sinless life on my behalf, died in my stead, arose three days later, ascended to the Father, and is coming again." That's the gospel per 1 Corinthians 15:1-4 that Ben and Roger mock by saying some can be converted without it. That's mysticism.
Also, the Primitive Baptists, who hold to the TULIP, believe ppl are not saved by the gospel. They say the gospel gives light to the Christ, who saves them. I have a dead friend who is an Old Regular Baptist that is of the Primitive Baptist faith and order, and he, and many others, stated that ppl are saved without the gospel. That's rubbish.