Partner status on JAL is a bit further out in to the horizon than you indicate.. You first have to qualify as Diamond in 2019, then wait for the service selection for 2020. And your partner needs to be a JGC member to be elevated to same status as you. So practically speaking, I would not put that in to the equation.

JAL requires 50% of the qualifying points to come from JAL coded flights. If you book an AA codeshare on a JL operated flight it does not count. But then again, a JL codeshare on an AA operated flight does count.