Oh yeah. I'm not saying that's the only way things can go off the rails. But with regard to "When Prophesy Fails" specifically, TFA says:

"A new paper finds a different story in the archives of the lead author, Leon Festinger. Up to half of the attendees at cult meetings may have been undercover researchers. One of them became a leader in the cult and encouraged other members to make statements that would look good in the book."

Unless I recall incorrectly, they were undercover researchers in Festinger's employ. Not that many researchers happened to converge on the same very small, obscure cult.

But perhaps I misinterpreted you? I took the impression from your comment you thought several groups of researchers were stepping on each other's toes, but reading it back, I see that you didn't explicitly say that. So perhaps I read that in.