Those people have been literally living in a dome. It would be easy to convince them of anything. They don't necessarily know that an airplane landing can be a bumpy experience, let alone a spaceship.
In our own world there are people who believe the Earth is flat, vaccines spread autism, airplanes give off mind controlling chemtrails...
For one time fictional events, we have plenty of examples of people being convinced despite a considerable amount of nothing happening. Think of end of world cults. One of the most famous ones predicted the world would end between 100 and 150 years ago and when it didn't, the higher ups of the cult said "it DID end, we are in a new world now". People still believe that to this day.
So for the dome dwellers, you could just say that there was no bump because maybe the ship teleported, and a yone who claims that the ship was always there is either a paid actor or some gullible person fooled by the Illuminati-run NASA.