So wait, You sold kooky a account, Then he hacked a different account that you owned?
Like you sold him a bank, then he hacked your main account. Thats at least what I'm getting from this.
If thats the case and you didn't sell him dadres1(or what ever it is ) And you sold him dadresbank ( or what ever you call it ) Then kooky DID hack your account. Because going into a account you don't own and changing the stuff is hacking.