The kid may not know it's an issue (although I think it is, to some extent, or at least relevant information). I didn't really realize for a long time that some people knew what they were doing twisting past a full. My brain catches up to my body at some point. When i take off I have no idea what's going on, but there's some point in the air where I can find the landing, or more like my body just does it. Again, unless it's a serious issue, I don't think you're going to be doing vestibular rehabilitation. You're just going to have to manage it, but there comes a point where it may need some consideration. For example, for me doing a front out of anything past a 1/2 took some extra work. Again not knowing where I was until about when I landed a 1 1/2...became an issue. Just lots of tumble track and bounders/flysprings out...and keeping up with the 1/2 punch fronts to reference that. If the kid tends to have issues I think this is really important. Do not go on if they can't show you a 1/2, 1/1, etc. They need to figure out how to "memorize" this in my experience. I have heard of very few cases where the vestibular issue presented later on and the kid had trouble doing say, a back tuck, because in the slower rotation she felt like she was twisting (basically the issue was different levels of pressure on either side of the vestibular system...in this case a very significant difference). She could do double full and double back. She did some vestibular rehabilitation (BY AN EXPERT) but they ultimately managed it by adjusting how she trained, warmed up, etc. The coach is actually a research scientist in biomechanics (lucky, right, if you're going to have that problem) and he explained that he spotted her on some skills because then she could use proprioception to figure out where she was. This was a very extreme example though, but it made for an interesting talk, especially given the capability of the coach.
Unfortunately most of us do not have this specialized background. The best we can do is to be aware of this issues so that if they present themselves we can perhaps contact someone who is, in order to manage the issue.