James couldnt assume it was Benignus that will be kidnapped nor Harobes who was afraid of blood.
One of the downsides of a fast paced story is that the author has to leave out a lot of details that provide context. That is where your skills as a reader have to come into play. You need to start assuming things the author intended without getting it wrong. If done right, it can make for a good experience rather than a frustrating one, unless you hate mystery genre. Kur pulls it off, but once again you need to rely on some of your own wit. IDK if it is intentional or not, but things slip out after the fact (eg James wiped himself before meeting Dylus outside, they came in, and he got dressed for the new queen's coronation party. Only after the party does he mentioned he took a bath sometime between coming in and getting dressed. So Kur gives us some warnings that extra stuff is happening in the background, but we just dont have the time to experience it and take in the full context).
I believe the king was interested in martial arts rather than fisticuffs. The choke hold James uses is impossible to get out of if properly executed. A similar one is called rear naked choke hold, where the trick to it is ruining the balance of the person being choked. To them, they are too focused on their balance that they cant fight the choker. To a spectator it seems like theyre just sitting there taking it like a moron and wasting precious time. James wanted his job to be a martial arts tutor, so I guess he got what he wanted in the end. You just have to let it go and accept that the king fulfills the role as job-grantor in the narrative for James to like him a bit more. It's not perfectly logical, but it is great storytelling if youre willing to suspend some disbelief, as one usually ought to, coming into a world of talking animals XD