Jack has covered most of the bases, but there may be a few more clues at the Amherst Library. The library web site has an "obituaries Index" for obits published in the Amherst News Times. This is a small weekly newspaper that is not part of the Ancestry Newspaper Database. The index contains the names of a number of the Nickel family, including several who appear in your posting, including Elmer Nickel who died in Indiana.
The index provides only the person's name, age, cemetery where burial occurred, and the date when the obit was published in the Amherst News Times. If you think there may be some information in the obits which you don't already have, you should be able to get copies by contacting the library.