FlyerTalk Evangelist and Ambassador: The British Airways Club
Join Date: Jun 2008
Location: Somewhere between 0 and 13,000 metres high
Programs: AF/KL Life Plat, BA GGL+GfL, ALL Diam, Hilton Diam, Marriott Gold, blablablah, etc
Posts: 33,194
The vast majority of cheap tickets (of which N is likely to be one) with both AF an all other airlines I know of are non-transferable or only transferable with huge penalties. To know whether your cousin has been exceptionally lucky and got a ticket which is transferable one would need to look at the actual ticket conditions, which he must have received (from AF or from his TA) or which could be retrieved from the full booking code (there are hundreds of different fares booking into bucket N so one would need something like NKXP16US or NKXB67US etc