So for all happy people who fall over this Thread I found a working solution to complete both Quests. Took me a lot of trying and my Henry was stabbed dead, more often than I want to admit 
Summary
When you get the Task Hare Hunt of Nicolas, talk to everyone in Talmberg, really everyone, ride to Andreas and get the Quest Sheep in Wolf’s Clothing. You can continue this quest, till you have stolen the hunting horn. Then talk to the Huntsmen’s wife and go to the meeting spot with Hanekin (hope he is called like that in English too). You can listen to his whole story, where he tells you that Diwish freed him, cause that will explain a bit what’s coming up next. After talking or not you HAVE TO ARREST HIM, BUT DON’T KILL HIM. If you managed to arrest him you will be teleported to the castle, wher Nicolas gives you money and Hare Hunt is completed. After that go to the Black Lukash (again hope you know who I mean) and tell him you have te horn. Than meet up with the poachers, after the cutscene with the guards, kill the guards, you will automatically stand on Hanekins side. After that, you meet up with him at his hideout and you can begin the quest to expel Nicolas and become Master Huntsmen.
I know I mangaed to come to this, because of a little bug in story scripting, but Hanekin explains to you why he is still alive and free. So I just imagined, that Diwish freed him again, hoping that he finally will desapear, what he will in the end when you are Master Huntsmen.
To Warhorse Devs:
In this Questline there is so many potential to do both quest, when you can implude Diwish for example or even
Summary
free Hanekin yourself
but, I am looking forward that you will do your best on improving the game
Flowbro
EDIT: I wrote this before I completed Cherchez la femme and unfortunatly I must admit that it doesn’t work as I dreamt of.
Nicolas won’t talk to me about the documents.