In october 10, waiting period was 8 months for diesel dzire, Dealers were selling the cars sent by ms il company for a pirticular custemer, to influencing custemer, there by leading to such scenario.
Dealer must inform the custemer about the follow up of the booked car.
Dealer must notify the custemer about discontinuation of the booked car model, should show courtesy to refund the booking amount or allow to change the booked model.
It seems , he hasn't done so. You can send him legal notice with or without lawyers help. Dealer will definitely budge ,Please see wheather proper booking procedure was followed by your cousin or not before it.
In case of long waiting period, custemer is always at the mercy of dealer, that is why I kept verna and dzire, swift at bay at the time of booking my new diesl sedan.