Yeah, something weird is going on there. 72 years at birth for the Amish sounds absolutely crazy too. Maybe the Amish one is life expectancy at 5 or 20 and the other at birth.
It's possible that they simply have much lower rates of infant mortality. The linked discussion is from pay-walled researchers, so hard to see where they discuss their methodology.
Low incidence of alcohol use, strong communities with a tradition of midwifery, narrow genetic pool (which would tend to exaggerate any gene pool effects) are all things that could contribute to lower rates of infant mortality.
Low incidence of alcohol use, strong communities with a tradition of midwifery, narrow genetic pool (which would tend to exaggerate any gene pool effects) are all things that could contribute to lower rates of infant mortality.