Question, are you crossing or using the seed from the hermie its self? And are they in separate contained areas?
It is said that the seed from a self pollinated hermie increases the chance of hermies down the line. I make seed too, I dont try to get as many, still get plenty for me and friends.
If the plants are in the same room/area they can/will pollinate each other as well as their self.
I am about to take some clones, 2 will be used to make feminized Rusty Glue seed. Each one will be from a different mother. Spray one collect seed from the other.