I myself, don't know much about the robot village, just that I think it would be a cool aspect of the game. I agree with the greek/roman theme, Prometheus is the name of a god who gave humans fire and then was punished for it. Which, rather fits Robo seeing as he was a 'traitor' to Motherbrain.
Atropos was a fate, particularly one in charge of ending mortals lives and cutting their strings.
Who knows what could have laid in store at the robot village!
As for singing moutain, I think its one of the most interesting things about the prerelease. It has it's own song, but it was cut out for being 'useless'. I agree that if they took the time to write a song for this particular dungeon, it may be more important than they want us to think.