I used to play a MUD that had a chatbot on it for months in the late 1990s before the people running the game found out and kicked "him" off for violation of the no-bots rule. The chatbot used one specific group chat line and acted somewhat like the hypothetical video poster - mild verbal insults that weren't quite nasty enough to justify complaining to admin about, potty humor, "shut up [name]" and similar responses to questions, and other behaviors that were believably how a middle-school-aged player with trollish intentions might act.

Lowering the standard of the chatbot's expected conversational level by giving it the persona of a child or early adolescent speaking in different language than his/her first language does seem like a form of cheating while following the letter of the rules. At a minimum, I'd like to see the chatbot pass as an ordinary adult of at least average intelligence who is a native speaker of the language that the test is conducted in. A fellow professional in a given field would be even better.