Let me explain how it forms chloramines and maybe that will help you better understand. During the regeneration process you soak the Purigen in a 50-50 solution of water-bleach. After that stage is done you soak it in a dechlorinator, to remove the chlorine from bleach. If you add an amine based polymer at this stage it will combine to for chloramine. Chloramine is a bond between chlorine and amine.
So you are correct in your aquarium you can use anything, just not in the regeneration process.