If I am not mistaken Qasar is not an option when you are not travelling and you are near your home place. And Qasar does not relax the timing of the prayer but the duration (Rikats) of the prayer.
And for people who say their prayers in planes and trains in aisles genius people
, well I don't know why they do it but if the circumstances are such, I can offer my prayers while seated I don't see how that is not possible? And in trains the berths can be used. And after looking at pics of deck provided by Jungibaaz, I would say that couple could have shortened their trip and said their prayers in some appropriate place.