I have myopia in BOTH eyes, and astigmatism in my left eye. Interesting, but...
The autistic individuals may have been glancing away, even if not aware of it. Calls for more research, but that is usual..
I can tell you for me though, most of my tie-ins with ASD are sensory hypersensitivities. One of which is a definite aversion to bright light. I did/too tend to squint a lot. Could this also factor in? And there, another area on this you could/should research.
Sincerely,
Matthew