Another one that I had no information, but came back a few months later with fresh eyes. Seeing that he went to Central Normal College, I found an article that said he was from Auburn, Illinois. A search into census records lead to a possible identification, but considering how common his name is, I needed more confirmation. I checked the parents of the suspected-Dave and found his mother's obituary. From Auburn herself, it mention her son was a Central Normal student. Bingo.
I even added a photo I found.