What a wonderful, expressive letter!  I regret your sadness at viewing the photograph of the Fort Apache students but certainly understand it.  None of the students in the photograph smiled either.  Yet, they should not be forgotten and sharing their images seems important.  Unfortunately, the collection is very small and I know of no published works about Mr. Stanion.  It may be helpful for you to refer to the American Indian Science and Engineering Society which actively pursues education for Native Americans while respecting cultural values.