This was probably the easiest thing in the world for Trump. He said “Look, you can be a rich man. You can be the man who led your country out of oppression. The world is your oyster. Just do what I say. If you don’t then you’re going to continue to have nuclear “accident” after accident until one of them kills you. Your choice.
Even if it falls, this summit is the beginning of a process, not the end.
Few people in 1986 foresaw Rekjavik launched a series of events that in five years, ended the Cold War and brought about the dissolution of the Soviet Union.
Trump and Kim are making history between two hostile countries.
I imagine it has gone very similar to what/how you have described.
An easy choice, for Lil Kim, really.