Noone can prove a thing didn't happen!
The onus of proof is upon the authors to demonstrate HOW they know such a fantastical claim is true.
If I published a paper saying "A mumsnetter orbitted the moon today and returned home in time for tea", the onus is not upon others to prove that this didn't happen, but upon me to demonstrate how I am certain of this claim, and why, if I have evidence that this happened, I failed to disclose it in my paper.
Science reporting is shocking these days.
I can't believe how many newspapers have written about this when the paper says nothing more than "this thing happened, we were told"