lelizwe wrote:(I think Mancina could've also been responsible for some of the magic; if you listen to his score for Brother Bear you'll notice how well he is at producing chants)
It's a bit hard to find more evidence of much ghostwriting other than vague "additional music" being credited to some of the contributors of the score, but if I recall correctly from Hans-Zimmer.com, someone said that Mancina was the one who did the "Simba, It's To Die For" and "Nala, Is It Really You?" cues.
I wouldn't be surprised if that was true, given that it's a more quirky-oriented befitting of his sort of material, and the grandiose action segment of the cue that plays when Nala chases Pumbaa and fights Simba does sound a bit more distinctive compared to other "epic" segments within the score. Even though Zimmer didn't truly establish his particular sound until some time later, you can definitely tell it's his handiwork in some of the other action material, but that fight music has a different feel to it. It fits in pretty seamlessly overall, though, especially when you hear him arrange some of Zimmer's motifs in there to thematically tie it all together.
I think the same post that stated all that also mentioned that Nick Glennie-Smith did some arranging in "Didn't Your Mother Tell You Not To Play With Your Food" and the second half of "Hyenas in the Pride Lands."