walking the track from Hagen towards Hagen-Heubing i hit a wall just west of the left spur down into the diesel-only steel yard. Hagen yard is immense with remarkably few flaws ... as is most of the line from Wuppertal ( annual plants growing through massive concrete retaining walls aside.) The wall impedes finding the challenging collectibles .... but a fast hop to H-Heubing did thevtrick.
there is a bridge over a small river there ... the east end of that bridge seems problematic... you can get thru going east by actually walking on the sleepers coming from Hagen-Heubing
This is an old, old route now even by TSW standards and the chances of DTG ever revisiting it are probably less than zero.