Mites are easy to kill it's the eggs you need to make sure get killed.
PAM will do that for you.
I've never used anything but Permethrin products to kill mites and it works wonders used properly.

I would suggest to him that maybe they came from him and maybe not, but it might be best for him to check to see and make sure he doesn't have them.
But honestly if he has them bad enough to spread them to you, he already probably knows.