I don't know if HJO needed better direction, but I do think the Re:CoM case could have been handled better. They didn't even lip-sync the cutscenes, which I think is just as distracting as Sora's voice because it required the actors to truncate their lines in an unnatural manner.HJO's voice changes a lot, I notice. Young Sora sounds completely different from older Sora, and it's really awkward to hear Old Sora's voice come out of young Sora's mouth in Re:COM. Either Haley needs better direction, Square Enix needs better editors, or they need another actor entirely to distinguish between the two drastically different voices.
But anyway, by Re:CoM, HJO's voice has... how do you say it? Broken? Cracked? Either way, he wouldn't have been able to recreate the young-sounding voice he did in KH1. I think the closest he would have gotten would be similar to what we've heard in DDD, but still, it wasn't as young as his KH1 voice.
I can say this because I've tried emulating my younger self's voice and it sounded like a cat getting run over by a car.