Re: "he didn't dare put anything into a company calendar"
He could just have written something innocuous, but just indicative enough. Like something with "BBC documentary" in the subject, so that any examination wouldn't raise any eyebrow, but "Bob" would have understood.
Also I don't understand why he didn't just shared his torrent while he was at work, so that to not impact his gaming sessions. And in his case, adding max upload speed would have been a good idea.