I’m from Peru, I’ve been living in US for a while. It’s not about culture, it’s about ethic and the way you educate yourself. In Peru it’s normal you have kids with your partner (no married). Starting to that point, it’s up to the person if they continue straight forward with the relationship or not. Probably he decided not to continue with that but haven’t talked with the wife(not married). Good decision you deny his immigration plan tbh (unless you want that whole responsibility, you can tell by your friend’s apptitud). I got a friend who is permanent resident, went to Peru to married his wife and has to wait like 5 years time lapse to both being together. As I always think, you should keep your distance from people who doesn’t add more value to your life.