Glad you liked the book! This may be completely made-up, but doesn't Joyom sound like jolom (head/village)? I wonder if it's not an imitation of some kind of difference in pronunciation between the two languages (e.g. an imitation of how Todosanteros talk.)

I did some quick calculations and if women have kids at 15, that puts 5 generations between 1932 and today. If there were 85 people back then, and each couple had eight children, that alone would bring you pretty close to today's population. Of course, back then they probably didn't have enough resources to have eight children, but they sure do now.