I've read all the individual statements by the authors and they don't even try to explain how this happened, they just vaguely bemoan their own trusting nature and deflect.

I don't see how it would be plausible for the insurance company collecting the data to independently tamper with it in that specific way (and getting the typeface wrong) before passing it to the unsuspecting researchers.

Oh, and of course they immediately taught the result to MBAs and executives. I wonder how long it'll take to filter out of the system.