Follow-up: I did reach JAL eventually. Agent took the info and sent it for pricing. Spoke to them today, Some airline split the record (there are two of us) and deleted some flights. Also, JL agent said most of the codeshares need to be rebooked as prime flights (at least JFK-LAX, LAX-YVR-LAX, SIN-KUL), which I really wanted to avoid because of the poorer earnings when credited to AA.