Thank you! So, uhm, I thought it was clear enough, but that is always hard to know if it is your own game.
You should drag the cage to the upper left corner and release it there. The screw will always move a little counterclockwise and it gets off.
I was searching for a fun way to get it out of the cage, so I decided to do this through a banana the animal eats so it gets too big for the cage and break out.
And in the end there was a hammer you threw around with the animal and break everything.