User error. I had inadvertently turned off “header menu” under “Theme Locations” while trying out the different menus. Everything looked similar, but it had reverted back to the menu with out my custom Navigation Labels (and was out of order too, which is how I finally noticed). When I switched back to the Responsive parent theme, it worked because I had set them up previously. I am an idiot 🙂
Thanks for the help and sorry for wasting your time.