I think it is really clever that this level works with two non-trivial solutions despite a lot of the terrain being steel and the two skillsets being very different

.
Green route: Not solved yet, I did find something I think works but I was 1 pixel away from executing it when trying to join the fencer to the top area - I imagine if I adjust placements a bit I might be able to find a way to join things up.
Red route: Replay attached - I initially planned to send one worker lemming to do all the work but then realised later I could use a lemming from the crowd to hit the most difficult button and send two lemmings off the bridge.
Out of interest, did you design this level with one route in mind initially and then adjust it to add the other, or did you plan both together?