Jeff Sexton
For those that can't possibly read about animals being in any degree of "harm" at all, know that war dog handler Tucker and his dog, Kane, play major roles here - and indeed, some of the more inventive while still realistic roles in this tale.
As for the "Much More Real Than Previous Attempts" bit, in The Last Oracle Rollins portrayed Autistics as damn near superhumans, with almost god-like abilities. Here, the Autistic character - a different one, and seemingly the first one mentioned at all in Sigma since Oracle - is a much more grounded and realistic Autistic, complete with hyperfocusing, rambling, self-recriminations, blowups, sensory issues... and no real meltdowns, which is perhaps the only "not-real" aspect of this particular character. In other words, at least in regard to Autism generally, Rollins shows tremendous growth over the last decade or so and is to be commended for showing how such a person could be a benefit even in such tense, potentially Apocalyptic, times.
Overall, this is going to be a particularly divisive book mostly because of just how fantastical it does get at times, but I thought while reading it that it worked perfectly well within the story - though even while reading it I was thinking it was a touch fantastical, and the Avatar notes in particular were unavoidable even while reading - and this was a solid several hours of pure escapist fun, no matter the exact bent of the genre of the story. Very much recommended.