As long as you put your FFP number in when you did the booking, you should be fine. I've never had JAL look at my card ever, they base everything on the bar code on the ticket (expect to scan yourself in at the Sakura lounge). Your OW status should show on the ticket. I do the opposite of you and fly AA for my US domestic flights, and it always has my Sapphire status on it along with the generic "Priority".