Is there such a thing as an honest cookie stuffer?

Ok, I just received an email from one of my "affiliates" - I won't say which product it is, but in the email the affiliate proceeds to tell me that he's been using a method that he has recently discovered may be stealing - called cookie stuffing. He says he's filled with regret after finding this out, and wants to send the money he stole to my paypal account, plus an extra amount for my forgiveness. Now the amount he made wasn't a lot so don't you newbs get any false ideas from this. Plus the amount of effort you put forth stuffing cookies, can easily be put into a legitimate method that will make you even more. But anyway, here is how I handled it:

My answer to him was to just forget about the payment, and to just not do it again. My reason for this is because if he was cookie-stuffing, then he actually wasn't stealing from me, but from my other affiliates. And there's no way of actually telling who he stole the money from.

I don't know if the way I handled it was the best route, so now I'm looking for wisdom from the warrior gods. How would you have handled this situation?