Frankly i’m little sceptical about this. This is what OW says:
Access to more than 650 airport lounges (with one guest) when travelling internationally*, including premium First Class, Business Class and frequent flyer lounges, regardless of the class of service flown that day
*North American itineraries within or between the U.S., Canada, Mexico (except Mexico City), the Bahamas, Bermuda and the Caribbean are not considered international destinations.
Has anyone got personal experience ?