I'm in a similar situation, but my one world status is through Royal Air Maroc. I know I'm eligible by letter of the law to access the BA lounge at JFK T7 or the BA lounge at IAD on domestic only itineraries, but in practice does anyone know if the lounge dragons at BA lounges follow oneworld rules?
(I've always been fine accessing AA flagship lounges and the oneworld lounge at LAX on domestic flights, but never tried BA)