You already got responded on what can be shiny and what not. With the informations you were given, you can easily tell what can be shiny and what not by checking the available shadow Pokémons in the games:
https://bulbapedia.bulbagarden.net/wiki/Pokémon_Colosseum#Pok.C3.A9mon
https://bulbapedia.bulbagarden.net/wiki/Pokémon_XD:_Gale_of_Darkness#Pok.C3.A9mon