Uncertainty over whether the situation is described accurately could also be uncertainty over whether the world works the way you think it does. So I think it's rational under many circumstances to take the one-box. But I don't think the video should have presented it as a valid EU-maixmization based chain of thought using the given probabilities. It's much more likely driven by unstated notions of risk aversion, ambiguity aversion, and regret minimization.