Although they are difficult to find, DKC3 does have hidden caches in various levels throughout the game (exactly 24 of them). These caches are quite unlike DKC's, and are still undetectable even after turning off the sprites layer in ZSNES.
They all seem to operate by means of an auxiliary object that spawns the item when it is pounded with Kiddy Kong, and changes the tile index of the nearby tile so that a hole appears in the floor.
PNG Snapshots!
DKC3_Cache_Locations.zip
Individual screen shots of all the hidden caches in DKC3.
(489 KiB) Download Size
This is a discussion topic for these "new-style" hidden caches.