Does Trump deserve credit for this?

Yes, he deserve credit for this, not all the credit - but some. Trump's response for NK (leader) was very public, and it's very naive to think he did not have any think to do with the situation.

What's really going on here?

Pretty simple, two counties, with population of just one nation, on their was of making peace. Do we know everything about this? no.

But it's doesn't matter, cause money important goals already been achieved. And either this would be a success or fail it's importance is in showing the world that steps towards lasting peace can be applied between countries in just days, it usually takes just a month for anyone to mostly get use to some radically new situation. Middle Eastern countries should learn and apply.