You really need to talk to the outfitter or guide and see what caliber of hogs are down there where you’re going.On paper I would stack my son up against any 10 year old and most adults, even adult hunter-shooters.
On game, he gets the big buck jitters whether its a buck, doe or squirrel. And the only way to get him over that is time afield, which we are working on every chance we can get.
The .223 with quality (non-frangible) bullets will work fine one pigs up to about 150lbs if shot in the boiler room. But if there are pigs down there like we have here, you can kill it with a .223 in the boiler room, but you won’t likely recover it. Bigger pigs with a .223 require a CNS shot to drop. And since your son gets buck forever so badly (so fun to watch!) you shouldn’t put that constraint on him to be so precise or risk (likely) losing the animal.
Pigs might not be M1-A2 Abrams. But big pigs are on par with Sherman’s. And they require a good kill shot.