One's right. The Kla"m"ptrap one is. Kaboom isn't in Donkey Kong Land 2 at all.
Answers (note that some are what I think are mistakes);
*Kaboom - Erroneously listed as Kaboing (also its description).
*Kaboom - Not in Donkey Kong Land 2.
*Klamptrap should be Klaptrap (you got that one right).
*Kutlass isn't in the game at all.
*Not quite an error, but the descriptions are all taken from the Donkey Kong Country 2 manual.
*Crocodile Island is called Crocodile Isle.
*Klubba is more of an ally than enemy.
*Krook "rockets" his hooked hands (means he does it at like rocket speed which he doesn't).
...and I think that's it.
I'll do a common knowledge one for ease (spoiler for size);
Chibisai Kong