That's exactly what I think. I can't begin to fathom why anyone would think that he does. Because of the ridiculous tweets?
The obvious reason for the increased discussions between North and South Korea is that China has been less and less supportive of North Korea - a trend that started long before Trump took office - and Kim Jung Un isn't an idiot. Without China's support, North Korea ceases to exist. The only way for Kim Jung Un to survive with any measure of power is to make nice with the South.
Trump has absolutely nothing to do with it.