They Like it tight... so if Your new hide will give him too much space he will be feel more secure sitting between hide and wall of cage/tube.
My Adult YB is same way... on his chunky side he sitting in hide.. after few moths off feed when he lost some weight he prefer tight space between hide and wall of tub.. after gaining couple hundreds grams more he is back in hide.

If You can find something smaller but big enough to contain him try that.