Please note that, according to oneworld's website, OP is entitled to use the Flagship Lounge in JFK T8 (
http://www.oneworld.com/ow/ffp/loung...lass-of-travel).
Customers flying in Economy class on the domestic or intra-European segment to connect to or from a oneworld longhaul First or Business Class flight can also use the lounge applicable to the class in which they are travelling the longhaul segment.