Both Jaya and Samar were wearing car seats belts and when they had accident, they both gets thrown out. Seat belt is suppose to prevents accidents like this. The writers wanted to makes us believe that seat belts do not help.
I do not think common sense is something that the writers possess if the script is anything to go by. It seems to be a gross exaggeration of reality all in the name of "drama where even a show that is pure fiction is still unbelievably far fetched. They seem to make things up as they go along, thinking that their audience are a bunch of idiots that lack any sort of brain cells Sony has really missed the mark on this one. And to think they're also doing shows like patiala babes, it's hard to believe something like this was commissioned