That's the case for myDS9. Knowledge was the lowest index(123) on his SB-5. He was 8.7 years old, so he wasn't really "younger" though... I was also puzzled by the huge difference between verbal(18) and nonverbal(10) knowledge. He is 2e, but still......Do you know which subtest on the WISC-IV is equivalent/similar in measuring nonverbal knowledge skill?
My son had similar scores on the SB-5. He took it when he was 5 years, 8 mos. We also had a big discrepancy between verbal and nonverbal scores (NVIQ 119, VIQ143). The knowledge score (111) was very low compared to the other scores, and I believe that's what brought his overall score down (FSIQ 132). I'd love to find a tester who is TRULY experienced with testing gifted children. We really liked the psychologist who did ds's testing, but he told ds that if it was difficult he could say, "pass" b/c "he was way past qualifying as gifted." It's like he was trying to make sure he scored well enough to qualify for a school gifted program, but that was not our goal at all. We want true scores so we can understand our child. He didn't tell our son that until he started missing a question here and there and became slightly frustrated. I think he, too, was trying to make sure it was not a scary experience. Our son doesn't like things that don't come easy to him, so he just started saying, "pass," "pass," "pass" without trying if it took some thought to answer. I think, overall, we had a good tester, but looking back I wonder how much little things like that affect scores. I am considering more testing but not sure where to go.
Another interesting note is that ds was just diagnosed with ADHD, and looking back at his SB-5 scores, working memory was in the 75th %ile, much lower than the other scores as well. This is very typical/indicative of people with ADHD, and I wonder if he'd score better in this area now that the ADHD is being treated.
To the OP, I feel your frustration and am appalled that the tester was so condescending. I feel your frustration. Don't you just love it that you had the testing done only to wonder if you need more testing to confirm the results? Like Dottie said, though, it sounds like you can accept that your son is solidly gifted. That's where we are now. We know that ds is probably highly gifted, but we'd sure like to know more. Good luck, and keep us posted on what you find.