What time was the flight? Some routes have caviar on some flights but not others. E.g. CPT there is the EK772 at 4am which doesn't have caviar (DXB-CPT direction) and EK770 which departs around 9am which does. I think if it's predominantly a night + breakfast flight (departure after midnight and before sunrise) and not ULH it probably doesn't have caviar. Pretty sure HKG-BKK has caviar (or had, not sure the current status of the route)