It seemed to me that the German column was ambushed on that raised wooden causeway, so there was no easy escape. They were also not in a state of readiness, and many seemed drunk, so perhaps they were an easier than usual target.
Having said that, there was some suspension of disbelief required at the end - for example the kidnapped girl survived, as did the bush baby, the partisans' attack. It also grated a bit that there was a representative spread of Germans captured, which allowed the fine dialogue at the end.
But none of that took away from the horror captured in one of the most moving films of all time.

It's my understanding that the anti-partisan units were notorious for their crimes like this while not being good enough to be front line soldiers, so theoretically, in movie-land it's cool. In 1943 in Russia the Germans needed all hands on deck in places other than Belarus.

Sometimes for the sake of a good film you need to suspend your logical boundaries. By the time this scene came around it should have been clear to you that this was nothing like a documentary that it was a horrific acid trip and that factuality was not real important.
Did you have a similar reaction to Apocalypse Now? I hope not.

Well in the final scene(s) the partisans held a small group of Germans captive and were about to execute them, so they must have won some manner of battle with them. But, of course, that German unit didn't appear to be that large to begin with (and, as pointed out above, these guys were on a massive drinking and looting spree and thusly not best prepared for a serious armed encounter).
"facts are stupid things" Ronald Reagan

I somehow missed that the partisans destroyed the German unit?
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The partisans blew up trains and ambushed individual patrols.
This is generally true but not all troops had to be small. When a partisan in "Voskhozhdenie" (The Ascent) says to the Nazi investigator that only 500 people survived in his troop, the investigator is happy about such small number.

//..such a large German unit..//
after the murderous orgy accompanied by wild drinking, rape, looting, these "soldiers" were unable to withstand the wrath of a small group of armed men.
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