This case is very similar to that of James Dresnok - a low-level soldier who had disciplinary and/or life issues sees North Korean as a way to avoid any consequences or punishments for their actions.
It’s likely that his life will play out the same way. He’ll be interrogated by North Korea (but he won’t know much as a footsoldier), then used in propaganda efforts, and work as an actor or English teacher. He’ll be treated better than the average North Korean, which means he’ll get a mediocre but passable life.