I see nothing wrong with the attraction to feet, per se.
The problem is how this man is going to deal with it.
If he is so attracted to feet that he sins mortally when he sees a woman wearing sandals, then he is going to have a hard time getting to Heaven.
If it is just an eccentric aspect of his sɛҳuąƖity, then he is probably going to find a way around it.
We all like to look at the beautiful faces of young women, don't we? Yet we don't require them to wear burkas. I believe that feet can be the same. I have never heard about a man who sins mortally looking at a pretty face.