Who is the protagonist?

The protagonist in Thomas Wolfe's short story "The Far and the Near" is the unnamed train engineer. Little is said about him in the few pages of the story. We know that this engineer ran his locomotive daily between two cities. Every afternoon as he passed a certain cottage he blew the train's whistle as a greeting to the woman and her daughter who lived there. He worked for the railroad for over twenty years and never failed to send this greeting to the unnamed women.
The author does not provide much more detail about the engineer's background. We know that he was married and had children. We know that he was impacted greatly by his service as a railroad engineer, including the several tragic occasions when his train had struck people and other vehicles on the tracks.
There are only three characters in the story, the engineer, the woman, and her daughter. As the story is centered almost entirely on the engineer, it is easy to identify him as the protagonist. We, the readers, get to learn about his emotions, thoughts, and observations. The other two characters are merely vehicles to understand the journey of the engineer. The short story is focused on his idealistic vision and his eventual disillusionment. We never really know what the two women actually thought of him, or what they were thinking at all. We only know what the engineer interprets from their actions and behavior.