(Cue political jokes)
to justify the title, "how to confuse a moral compass" the methodology would have to remove the justification or public discourse aspect, and show that someone's internal or private belief actually changed due to the conversational obligation to defend what they are misquoted as saying. i.e. you would have to find out what they thought to themselves privately before and after.
maybe a way to do this would be to have an "outside friend" who is more trusted than any of the people involved in this fake context, and see if they would report a different opinion to this friend that they think has no connection or knowledge of the immediate social context, due to the misquotation in the immediate social context.
As it is,the methodolgy does not justify the conclusion. (as summarized for us, I didn't click through to the paper.)