score:9
With the picture material available I would like to challenge the frame of your question.
The picture seems to show multiple German soldiers in uniform (although only parts probably because parts were taken off for intensive labor) carrying what looks like it might be a dead body while an armed and properly, but differently uniformed soldier is standing in the front.
This would be highly improbable being filmed in a still working death camp. No German soldiers would have done physical labor with hundreds of prisoners around to be used as forced labor. And German soldiers would not need a guard.
What this most likely shows is a scene after the liberation of the camp where German prisoners of war were used to clean up the camps, removing the dead victims and burying them. An allied soldier is standing guard over them. From their uniform and weapon I would assume the guard is British. For example compare the obvious German cap in the left with the very British looking cap of the guard.
That explains why it's a British rifle in the foreground.
Upvote:4
Germany captured a significant number of enemy weapons (and in some cases fabrication lines) and issued them to second-line troops. As John pointed out in the link in his comment, the Lee-Enfield became the Gewehr 283(e).
Upvote:7
Apart from the Germans using quite a few captured weapons and other pieces of equipment, you've also been watching a Netflix work of fiction.
Are you sure the footage is historical that you saw, and not staged as part of filming that series? A LOT of WW2 reenactment uses historically incorrect items, most people never notice. And that includes a lot more than rifles. Aircraft, vehicles, ships, are all substituted (sometimes with fiberglass covers to make them look more authentic) for things they aren't.
And a lot more Lee Enfields and Garands survive than do Mausers.