I find your interpretation to be something of a stretch. The point is surely that the colour of the student chap's skin doesn't inform the story of the song at all and is a gratuitous inclusion. Had his girlfriend been spirited away by a white student, skin colour wouldn't have been mentioned. The line has been commented on many times. Either he never noticed that, so it never occurred to him to revise it, or he was aware of the criticism and stood firm, which, if true, could be telling us something about him.

As I said, I like many of his songs and I shall dwell no more on this aspect. All good wishes to his family and friends.