Of course it was set up... and maybe they're not arguing that at all. All they claim to have done here is gotten the single highest word score ever. I guess they did.
What's troubling is that it's these kinds of players who "cheat" when actually playing against others online or on their phones by using word generators. Arguing that is pointless. I KNOW you cheat.
The real test is getting these kinds of players on a physical scrabble board. They'd be absolutely eaten alive without the trial and error allowed in WWF.
All in all, and while this must have taken some time to stage, it's impressive that they were actually able to do it.
...but it's NOT a real score in real game. :)