I haven't checked the questions carefully, but in general classifying the kind of language I believe is undecideable, so the video could be showing a human doing something computers in general cannot do.
Another example of this: theorem-proving is undecidable, yet automated thoerem provers are definitely capable of solving simple problems. The undecidability result means that any given automated theorem provers isn't capable of proving the truth/falsity of all statements. But this isn't some crazy limitation - this is true of humans as well. You can solve some math problems, but if someone showed up with an exabyte-long statement about how a problem-solver-who-is-identical-to-you-in-every-capability solves problems and asked you to prove it, obviously you wouldn't be able to do that.