You will find we do not buy into cage aggression here and feed in our cages....well most of us.
It is very possible that its just not recognizing the f/t.
I would try to feed in the dark while being silent as possible. Then make sure that you are presenting the prey at a temp that mimics a live rodent. That will be around 100F.
If it doesn't take it while you dangle it or zombie dance you may try leaving it and leaving the room and see if it doesn't eat it then.