Welcome, jsr!
That is indeed an unexpected profile, but not necessarily worrisome. Do you have functional concerns about his reading? That is a much more important question than what the test scores mean--and may help us determine what they do mean. As I've mentioned before, test interpretation in the absence of the overall context of the learner is fraught, and should be both undertaken and received with significant caution.
But I can make some general comments based on similar profiles. Overall, of course, your child's cognitive ability clearly is extremely high, with all assessed areas above average. Measures of word-level reading (word calling, phonetic decoding), fluency and silent (probably) reading comprehension are all generally within ranges predicted by cognition. (BTW, if this was actually the WIAT-3 and not the -4, may I assume this was done a few years ago? Or outside of North America? If not, I should caution that the WIAT-4 replaced the -3 four years ago.)
Phonological processing (CTOPP-2) presents with comparable levels of strength -- consistent with general cognition -- in phonological memory and rapid naming, which are two of the three so-called pillars of phonological processing (and thus word-level reading development). As you note, phonological awareness (phonemic proficiency) is the relative low area, in the average range. That last point is a good one to give a moment to: the area of relative weakness is age-appropriate.
These formal testing scores do not support a diagnosis of dyslexia because reading itself does not appear to be impacted at any level. Which is, after all, the hoped-for outcome of dyslexia interventions. Does your child have some of the underlying phonological processing qualities associated with dyslexia? Perhaps. (If there is no other child-specific explanation of the average scores.) But having average phonological awareness skills at this age-level likely means they have sufficient access to the skills necessary for mastering reading. (After all, age-peers of average cognition with the same level of phonological awareness and much lower levels of phonological memory and naming speed master the reading decoding skills necessary to access adult-level literacy, with the principal limiting factors for them arising from vocabulary and language development.) Phonetic decoding growth curves in the general population rise steeply into fourth or fifth grade (which is around this age-level), and then continue to grow, but less dramatically, into early adolescence, where they level off.
In short, it is possible that your child has some dyslexic qualities, but they don't appear to be impacting the actual reading acquisition process, probably because the areas of relative weakness are still age-appropriate, and they are past the half-way point of adult-level phonemic awareness development anyway. By all means keep an eye on reading development and how your child experiences reading, but I wouldn't devote much anxiety to it!
