HIs job is not your responsibility.
I think the MD has told you about the not so nice chat he plans to have with your AH so you can "pave the way". But if you do, then that's not healthy for you.
You telling your AH about the not so nice chat is not going to change the outcome of the chat. You have no power over this situation.
I find the MD trying to tell you not to bring your AH to the party if he was drunk a bit triggering - you can't stop him getting drunk nor would you have been able to stop him coming to the party! Imagine if you had tried!