"Misinformation" ? Very unlikely. An entire flight full of people being confirmed dead does not happen through "misinformation". There are massive studies into this type of thing, and I think even if they found a plane full or corpses they would not stop looking for every single person if they did not have DNA samples confirmed of all the dead.

This type of crash, while every single person (or body) is unavaliable to you (being as many are still alive, many were cremated, some buried) is IMPOSSIBLE to fake. It's just impossible.