my babies who are actually 18 days old today (I counted the day they were born as 1 wk before SHEESH) would not stay in the nest box. So I made a shelter instead.
I turned the nesting box on its side with the biggest wall facing the opening of the hutch. This lets the kits in and out easily, lets the doe nurse easily and protects the kits from the cold winds. They love it! The would love a little hideaway like yours!