It's a ZDF documentary, I imagine DW only got the rights to show the translation outside of Germany.

Here's a link to the original: https://www.zdf.de/video/dokus/megacitys-wenn-es-nacht-wird-...

If nothing else helps, maybe https://mediathekviewweb.de/#query=Wenn%20-%20es%20nacht%20w... will do?