Thanks for the nudge, galun!
1&2. This DC also has some pretty big index differences, but I am not really concerned about learning disabilities on first look, as his lowest areas (VS, WM, PS) are very strong too. (These scores are not age-appropriate; they are on the border of Very High and Extremely High, around +2 SDs above the mean. Reasoning scores in this range would be considered impressively high in the general population.) It may be accurate to say that his memory/speed/output are relatively low (in comparison with his own abstract reasoning skills), but in absolute terms they are well above NT same-age peers.
3. The standard deviation difference is something to think about in terms of how remaining with age-peers and addressing his needs through in-class differentiation and enrichment. The main area of difference that we can document between them is that DC2 is much stronger in verbal cognition--which is most of elementary school. It's also easier for a motivated teacher to differentiate in the early years. But both of them are strongest in fluid reasoning, which can manifest in almost any academic skill area, since it's about conceptual understanding. Appropriate placement for a specific child also is dependent on many other factors, including non-academic ones (e.g., temperament, social needs/strengths, executive functions, family needs). Rather than suggesting a specific placement, I would encourage you simply to cultivate an environment where you and your DC communicate frequently and openly about how he is experiencing his schooling, so that you can investigate and problem-solve any challenges early, as they are arising, and before they start to compound. But as a generalization, the further outside of the norm a learner is, the more likely it is that they will need some kind of adjustment to the conventional school program.
4. As with his formal school setting, I would suggest instead simply presenting him with opportunities to explore and play with various topics and activities, rather than trying to tailor his experience toward any specific direction. His cognitive profile is actually quite balanced, and strong enough in every area assessed that where he thrives the most is likely going to be much more a function of what he loves than of his nominal scores. Follow his lead; what he responds to will tell you how to foster his loves and passions. He's still very young, and all enrichment really should feel like play.
5. Sometimes the asynchrony of very high academic cognition and, well, being six, can create social challenges that are perceived as behavioral. If the school has been supportive in the past with your other GT children, I would expect that knowing these current pieces of information about his cognition would help them develop more effective plans for helping him learn some more adaptive ways of navigating his classroom environment. You know the staff there best, but it sounds like you could be fairly straightforward and direct in letting them know that you also have been trying to collect information that might help with his behavior in class, and these are the findings your evaluator presented to you.
The typical (and simplest) intervention would be to have a school staff member (likely adjustment counselor/social worker, guidance counselor, school psychologist, or even speech therapist or occupational therapist) run a little friendship group with him and a couple of his classmates (or possibly a rotating couple of classmates), where s/he gently coaches all of them through social interactions while they engage in some sort of fun social activity (card/board game, working on a puzzle or creative project together, etc.). It's actually a pretty common situation for kindergartners of all cognitive levels (and even more so for these pandemic cohorts), so this should be a familiar plan for the school team.
The other dimension that might help with behavior is looking into additional academic challenge. If he has more engaging and appropriate (for him) instructional tasks, he might have less time and attention to fill with undesirable behaviors. What looks like his impatience with his peers might actually be an expression of his own unsatisfied hunger for more. Small children (even very bright ones) don't always know how to define their own discomfort. They just know that something doesn't feel right.
