Thanks SharraShimada and klei. Ruby for your suggestions!
The problem kind of resolved itself somehow. I tried manually moving dupes over steel that was lying around and they could move to it. However, while part of my qued up buildings was completed over the course of a long time, some weren't.
I had some steel lying around in one spot from decommissioned rockets, bunker tiles and gantries. And there was a ladder leading to the spot in question. Nothing was broken. But I replaced the ladder segments with new ones and whaddya know. My resource tab all of a sudden lights up with a couple tones of steel Im sure I had all along!.
Would it still be relevant for me to upload the save after it's been resolved, I kinda played on for another 300 cycles by now after my little issue was resolved. If so, how exactly do I do it? Same way as with pictures? (I'm kinda new to klei forums btw)
Thanks for your input guys!