Several studies and clinical investigations are published on functional foods in human health. But I am yet to come across any study on effect of functional foods to combat malnutrition in tribal kids.
Malnutrition in tribal or any group of children is almost certainly related to poverty. You are looking for published "battery of clinical trial data", which takes considerable amounts of money; who would be willing to spend this money?
Management of malnutrition by locally available and culturally acceptable foods is a matter of common-sense - the main issue isn't lack of studies which might empower some with magical ability to alleviate the underlying causes, it is about management of resources in a responsible manner. But then, given the human nature....