For Verika, I would probably use grey, and the brown you have.

As for Kazi, see what colours you can use on Mazeka, and replace the white parts so you have some for Kazi.

Actually I found left over Matoro Mahri parts and used them with Inika parts, I just finished Kazi, his weapon isn't that great though, it's what I wanted him to have, but I'm lacking one part that's properly colored, I have two parts I need, but they're different colors, so I had to use something similar, but loose, to finish his weapon. I also found parts for Velika, I forgot my Ahkmou MOC, so I'm using those parts.