Yes, but he would keep his army and gradually have more food for his people. The upside is that he would be more appreciated with his people having full bellies.
And trade would lead to more electricity Etc. I understand that he would have a problem with his labor camps and police state philosophy, but that is not something that we did.
He can stay alive with a treaty with us which we would honor. His troops would have to control the population. And nukes were there to threaten us, his people were never the targets of anything except the secret police.
A dictator rules because it benefits his top level supporters. If the top 15 or so NK generals stop getting paid, Kim is dead. A well fed and more prosperous population is rat poison to the top tier military in a dictatorship.