Others might be able to provide more detail by it's my understanding that good Bishop Williamson wisely teaches that boys require "rough" sports where they compete against one another in "hand to hand" combat style play. Running, getting dirty and sweaty seems to be a requirement.
Fencing in today's world is a co-ed sport and could not really be considered manly. Also the costumes are vulgar and are to be avoided.
Better choices would be soccer, baseball, cross country running, track, basketball, perhaps even boxing or martial arts under the right circuмstances.
You son wisely follows his God-given instinct to avoid an effeminate activity. You should let your husband decide what activities your son does. He is better suited to help your son develop his masculinity and that way you don't have to stress over it.
How about Catholic Cadets? There are no women involved.