Nej de er 2 forskellige kommentarer... Rex har blot en ARC pauldron som optjenes efter at have gennemgået den trænning. Kama'en mener jeg er det samme.
Den blå farve som kan "forvirre" forklare jo i starten af Klon krigene hvilken rang Klonerne har, blå så vidt jeg husker er Captain.
Desuden kan du læse det omkring Alpha i Behind The Scenes på Wookiepedia
"Behind the scenes
According to the Star Wars: The Clone Wars DVD's commentary, the creators at first had decided to put in Alpha as the Clone Wars series' prime clone character. However, Lucas objected because his inclusion would make too much of an alliteration (Anakin, Artoo, Ahsoka, and now Alpha), so a different clone character, Captain Rex, was created. "