That crane asset in Caestino was also a crane placed in Duscae in the 2014 red sky clip, which would imply they probably originally intended more cranes to be placed around places. Btw that same crane is also used in Monster of the Deep at a fishing spot which is supposed to be near Crestholm in Leide.
As for the red sky itself, I tried to get it to activate on the debug mode, and basically what happend was I was just flicking through different lighting settings until I saw the red sky one by chance, but the thing is the red sky was only active for about 1 hour in game which was only a few minutes, and it started around 7pm in game when it starts turning dark, then it turned red, then turned back to normal night time afterwards. I don't know why it was like that but maybe the red sky itself was supposed to be something related to a specific time within the game.