Down Below prevents you from going downwards if you're carrying an unconscious Contestant. While making sense on the surface (picking up a contestant changes your goal from "collect scrap" to "rescue"), this actually prevented me from successfully rescuing someone today, because if I had been able to take them down one level I could have brought them out in AceHigh instead of being cornered by FoeBots and forced to abandon them to save my own skin.
There's good reasons why you can't carry a fallen contestant downstairs. Most of all, players could be mean: If an unconcsous contestant is waiting for NewDay to get them up and out, you could carry them deeper and abandon them there to reverse their progress. Secondly, even if you make an honest rescue attempt, deeper FoeBots are tougher, so that makes you even more likely to have to abandon them to save your own skin.
I suppose in you specific case the exit was close to the stairs of the lower evel, so downwards was the nearest way out, but in general a deeper level make it harder for rescuer and rescuee alike.
Exiting clears DB of FoeBots. So you could leave the fallen contestant alone, map out the way up and out, exit to get rid of Bots, and then make a beeline to the unconsious contestant and rush straight out. That way you won't encounter all that many FoeBots while you're loaded down with the heavy contestant in your backpack.
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