I'm relatively new to the trad world, but every boarding school that I know of has had at least some degree of homo scandal there. There are probably ones that have not, but it seems to be a common theme.
I can only tell you what I would do in the situation. I would never send them off to boarding school. Way too risky for their souls. You would think that parents could feel safe sending their children to trad schools, and it should be that way, but it has been proven the opposite. These are crazy times, and it seems that no group is immune to the effects of this degraded society. Hold your children close, and teach them what YOU know is important. For if you don't, someone else will, and it may not be what you had in mind- and by then the damage will be done.
God reward you for all of your efforts in educating your children. Keep your eye on the prize, and I will offer for you a few prayers today. God bless you!