> Aside from that, when you have a world where the rules are different, it’s important to lay them out ahead of time
No, not really. Majority of readers have enough intelligence to pick up those rules on the fly as they witness them in action firsthand. “Laying rules ahead of time” is called “info-dumping”, and its a narrative tool that is rightfully criticized by both readers and writers alike.
That aside, game never explicitly tells that it try to mimick any sort of court. I’m not sure if you have noticed that or not, but societies in monster hunter universe aren’t exactly modern and progressive, and expecting a civilization that is stuck somewhere in stone age to be up to par to modern law rules is ridiculous.