I've long sung "Indigo" - don't know where I got that; I don't think it's my own corruption of "Ingo", but it could be. However, that may be, I've taken it for a corruption of "India" ... the idea being that the speaker yearns not merely to be far away but as far away as possible, on the other side of the world, and somewhere exotic, where he can be "alone in the crowd" and provided with distractions - if that's the case, then the name isn't terribly important, as long as it conveys that sense of distance and exoticism.