He's on 10.7, he's not going to downgrade to 9.2.0, as it's only risking more of a brick. If he stays on 10.7, he's going to be using a method to get kernel9 access that has not been thoroughly tested and hasn't been made to support 10.7, but has been made to support 11.2. That's why I'm saying he should update. What you're telling him to do, probably won't work very good. It'd be quicker and more stable if he did it through 11.2, but that's your thing if you want him to risk more of a change to brick or whatever.