not on the boarding pass, besides i don't think you want to mark up ur price, having boarding pass means u have checked in for flight.

I don't think its shown on the boarding pass what package u bought.

all mas tickets are assigned seats, you don't get to choose ur seat, but they choose for u, rather than being like sitting in the bus where u find ur seat in the plane.

price may vary on the same flight, it depends on when u bought the ticket, if ur cousin bought way advance, the price may be cheaper.

if you are unsure, u can always call mas ticketing office to confirm the price u paid for, I am sure they're willing to answer ur doubts, or u can ask your friend to produce the receipt for which shows the price she paid.