No, it's you who needs to reread it. He paid what he actually owed. Not what they tried to cheat him out of. The decision to let a collection agency do the negotiating was the hospital's. They could have made a fair deal themselves.
he didn’t pay the person that he owed, and he has no idea of the real amount of “what he actually owed”.
the amount that he paid was utterly unrelated to the services that were received. debt collection agencies don’t know (or care) the different between hospital bad debt and new car bad debt. it’s odd to think that a bad debt collector is going to magically arrive at the perfectly computed real value of a complicated medical procedure.