Even if its king would be mate in one, it does not matter, as you lost on time. As the engine varies, this variation will probably not be repeated. Kasparov can prepare for lines, as he usual does, but there is no guarantee that the engine plays these lines.

BTW, I also played a few games, 2400+ player on Lichess, I had no chance. My impression is that the claim by this author is correct. Or I am overrated :-)