In more-or-less order of your questions:
1. You do have the ancillary indices for the WISC-V (GAI, NVI, QRI, CPI). That's probably good enough at this point. You don't have any significant resources to access that would require more on those indices, especially since you are at the college-entry stage of your education, and already have very fine ACT scores.
2. To your fluency scores: all of your fluency scores are on the higher side, even in the context of your own profile. A 160 is certainly within your range, especially for a mostly automatic skill like word calling. Notice also that there is minimal scanning for that, which can expedite performance for an excellent reader. Remember that you also don't have to process meaning to score well on a decoding fluency measure.
3. Math scores. There are two principal reasons for scores lower than your WISC and WJ appear to predict.
Firstly, you may have heard of the concept of regression to the mean. Given the inherent measurement error in any test instrument, it is extremely unlikely that a very high score (far off the mean) will be obtained on two different instruments (or even on two different administrations of the same instrument, separated by time). If you look at the prediction algorithms, the 120 is within the range of predicted scores. For example, a typical correlation between the WISC and an achievement test (I don't have my tables in front of me right now, so I can't give you the real numbers, but this is within the ballpark) is about 0.6. So if you use the WISC-V QRI of 143, and take 43 x 0.6 = 26, your predicted math score on the KTEA is 126 -- which is exactly what you scored.
Secondly, your WJ achievement scores were obtained when you were only 8, at which point your age peers were only expected to have been exposed to the four basic operations up to single-digit multiplication, and the beginnings of division. THis means that, if you had any level of mastery beyond that, it was much easier to score extremely high in mathematics. Your more recent test, in middle school, would have expected a possible range of math instruction that could have encompassed, for example, algebra I for a much wider range of your age peers, so you would have needed skills at least into the geometry/algebra II range to score similarly high.
3. Your old test results are very consistent with your most recent results, especially given what I noted above regarding regression to the mean. The relatively (not absolutely) weaker successive/sequential processing performance on the CAS reflects the same thinking profile we discussed previously, where having the pattern helps you fill in the details (typically a more simultaneous processing style). One interesting note: your old WJ results suggest some mild vulnerabilities in the neuropsychological processes underlying basic decoding skills (phonological processing, visual-auditory learning). You appear to have found an efficient solution to that, either on your own or with interventions, which is excellent, but it likely explains why you continue to have very mildly weaker reading comprehension and writing fluency skills than other skills. At this point, I don't anticipate any significant impact on your future, with the possible exception of learning a second language with many phonetic exceptions or complex phonographic systems (a deeper orthography). Languages with shallow orthographies should not pose a problem (e.g., Spanish, Portuguese, Italian, Finnish).
I'm glad you find my posts helpful. Feel free to ask other questions.
