My instinct is also pulling me to think this kid is psychopathic, but drawing this kind of conclusions about some kid we hardly know anything about... it doesn't seem to help anyone. I would not read too much into the fish-catching thing either. I think we could at least say this kid probably does not score very high in terms of collaboration, right? I wonder if the kid just generally didn't show a strong inclination to seek help. If you don't want to get other people involved, sitting there just observing the fish might be a natural thing to do, and if you observe for long enough, realizing you can try catching a half-blind fish might just dawn on you. So I am not sure if this instance is that strongly related to intelligence.
Maybe we can say G-factor matters a lot in the woods if you are not very big on collaboration / playing nice. Humans evolved being social animals and the G-factor probably does not matter much if you are surviving in the woods with a group of other humans. In this case, collaboration and not being a jerk are vital for survival. But, imagine if that's not the thing for you. First, it means you are probably going to have a lot more alternative activities---like when other people are already having fun hunting together using tools that belongs to the group and you don't have a goto-person to get you integrated into the activity. You have to do something else. And if you are smart enough, that could still make you quite useful in the group as the eccentric R&D person. Though... if you are smart but too uncollaborative, then intelligence might actually save / extend your life when the group decides to throw you out.
With stories like this, I think it's important to also resist the stereotypical myths that being extremely intelligent and being not-very-nice are correlated, or somehow intelligence alone is enough (I am not anti-intelligence and I think it'll be good if everyone can get more of it). Resisting this myth is important because the opposite is dangerous. Someone who is both smart, collaborative, and has a genuinely kind heart will probably do best. And someone who is smart, knows how to act collaboratively, but is slightly “misaligned” in some other ways (e.g., out to maximize their own gains over the long run) will be effective. Then, someone who is smart, but fails to even pretend to be collaborative and cannot act as if they are nice will... get thrown out of the group pretty soon. In an actual forest situation, they might last a bit longer than usual, but probably not long enough to reproduce again. So I'd say G-factor is not necessary or sufficient in even the forest.
I had a surprising experience with a 10 year old child "Carl" a few years back. He had all the stereotypical signals of a gifted kid that can be drilled into anyone by a dedicated parent- 1500 chess elo, constantly pestered me about the research I did during the semester, used big words, etc. This was pretty common at the camp. However, he just felt different to talk to- felt sharp. He made a serious but failed effort to acquire my linear algebra knowledge in the week and a half he was there.
Anyways, we were out in the woods, a relatively new environment for him. Within an hour of arriving, he saw other kids fishing, and decided he wanted to fish too. Instead of discussing this desire with anyone or acquiring a rod, he crouched down at the edge of the pond and just watched the fishes. He noticed one with only one eye, approached it from the side with no vision, grabbed it, and proudly presented it to the counselor in charge of fishing.
Until this incident I was basically sceptical that you could dump some Artemis-Fowl-figure into a new environment and watch them big-brain their way into solving arbitrary problems. Now I'm not sure.
His out-of the box problem solving rapidly shifted from winning camper-fish conflicts to winning camper-camper conflicts, and he became uncontrollable. I almost won by breaking down the claim "You have to do what I say" into "You want to stay at camp, here's the conditions where that happens, map it out- you can see that you're close to the limit of rules broken where you still get what you want." This bought two more days of control. Unfortunately, he seems to have interpreted this new system as "win untracably," and then was traced trying to poison another camper by exploiting their allergy. He's one of two campers out of several thousand I worked with that we had to send home early for behavior issues.
In the end, he was much less happy than the other campers I've had, but I also think he's one of the few that could survive "Hatchet" or "Call of the Wild" style- despite comparative lack of experience.
Addendum: he harassed and kept catching the poor half-blind fish for the duration of the stay, likely because he got so much positive attention the first time he caught it.