y'know ... I think my experience with handstand is comparable. I learned to balance rightways up as a child and don't remember much about the experience, which is why I didn't think I had anything to contribute to this thread, but learning to balance upside down is something I never could get as a child, and only learned a couple of years ago.

The first time I went into handstand my yoga teacher held my legs and I was so terrified I literally shrieked. It's still very slow progress getting my heels off the wall ... I think my PR is six seconds ... but before I hurt my shoulder I was plenty comfortable in headstand in the middle of the room, and I can go up into handstand at the wall pretty much effortlessly. It really was an ah-ha moment when I felt my body in balance. I think having the courage to try until they get that ah-ha is something they'll need to find within themselves, but it sounds like you're doing what you need to, to help them on their journey ...