[@Rilla]
You could have them THINK they were randomly displaced, and have them be wholly convinced that they were. Even going so far as to tell other characters that they were.

But it would be an untruth hidden behind sincere ignorance.

As nothing was really explained to anybody.

Shit actually.

[@Enki] That could explain your characters, just have them think that they were sent blind into a mission with all of their equipment.