Actually in the video on it he mentions how annoyed he was about the lack of a final boss fight and mentions that he was annoyed he didn't get a good ending for his actions. Either he played the game all the way through or quit and read ahead so he could pretend he did in a video complaining about the game. I'm betting on him actually having played the game through since he seemed legitimately angry at Yager for the game and I feel he'd have mentioned that he'd dodged a bullet by quitting if he'd read ahead.He didn't even finish it though. He got to the first time you killed Americans and went apeshit and quit. So like barely 4 chapters in. I would have loved to see his reaction to some good old White Phosphorus.
It also leads to the amusing implication that he played through half of the game in the hopes Konrad would suddenly turn out to be a Muslim infiltrator and the 33rd would join up with Walker to genocide the population of Dubai.