I had a baby Argentine who would never hide in her log. I tried a tiny flower pot and a small wooden hide box, but she wouldn't go for those either. She was very nervous and easily stressed when she first came to me, so I found a solution: A washrag. She immediately curled up under it and that was that. The extra-snug, warm feeling of the rag must've really helped. I would pick her up and hold her within the rag, and she was much calmer during handling too.