But it seems to me that a cobination of discomfort with certain sensory things, and change, along with a very concrete way of thinking, would all contribute
Absolutely. I've taught children with asd for years and we have had gender questioning children. You can absolutely track it as well as "special interests" of a gender stereotype (usually most obvious if it's a boy loving stereotypically girl things.)
And the the NAS have someone saying you are not to think this is a part of it at all (I think Joe Butler, there's a page on it.) and yet it absolutely was for one child we taught, who was seen by the Tavistock and did not need to transition. They and everyone around them, (including teachers), just needed things explaining in terms of sex and gender. But this was over 10 years ago.
Read about Temple Grandin's child and teen hood and it absolutely describes this process, not a whiff of trans. Just rejection of irritating impractical clothes and games, a love of cattle ranches and a feeling of sensory peace while around animals, cattle and their squeeze boxes.
I cannot fathom how anyone working with children with asd cannot see this!