We found a solution. Back to sitting at her door until she is asleep. Have scattered flowers around the bed as crocodiles dont like nice smells. Then the fairies in the garden told Daddy a recipy that scares pretend crocodiles and they made it together in a spray bottle so now she sprays it in the toilet if she is scared.
So far so good. But now she is not sleeping through in her bed anymore and she is back in ours for part of the night.