>>18458868
It was just a means to rehabilitate poachers (who were common because the Weimar Republic severly restricted the use of weapons and food shortages were common). There were 2 minor mythological aspects to it. One being the German king Heinrich I. who accorsing to some legends did rule leniency on criminals.
>König Heinrich war zwar gegenüber Fremden sehr streng, gegenüber seinen Landsleuten aber in allen Fällen mild; sooft er daher sah, dass ein Dieb oder Räuber ein tapferer Mann und zum Krieg geeignet sei, erließ er ihm die gebührende Strafe, versetzte ihn in die Vorstadt von Merseburg, gab ihm Acker und Waffen, befahl ihm, die Bürger zu schonen, gegen die Barbaren (= Slawen) aber, so viel sie sich getrauten, Raubzüge zu unternehmen. Die solchermaßen gesammelte Menschenschar bildete eine vollständige Heerschar zum Kriegszug.
The 2nd is the German hunting culture. Even the military adopted many of these traditions, to this very day many military occupations have the German word Hunter (=Jäger) in them: Gebirgsjäger (mountaneers); Feldjäger (Military police, though this name is a post-war invention, until 1945 Military police was referred to as Feldgendarmerie); Fallschirmjäger (Paratrooper), Panzerjäger (=oudated combat role, it were just infantry and tank units tasked with destroying enemy ranks).
There was a certain exspectation that the Poachers would do well against Partisans due to their experience in hunting animals too. But because there was not a sufficient number of Poachers to actually made a proper anti-partisan unit, they just added a bunch od foreign collaborators and court-martialed soldiers to the units and made them into an assault battalion.

>>18458868
nazi high command were fighting to extend their lives for a few months or the minute possibility of horrifying their enemy so much they agree to a ceasefire just to end the carnage, they emptied the prisons just to scrape together a little more manpower, a veteran and professional officer like dirlewanger was first on the list