Hmm. Josh Brolin as a Comanche? I seem to remember reading he was from Swiss descent.
In regarding to casting news, I suspect the likely casting of unknown young actors for the lead roles of Kee and Taabe, with the latter being an underage child, isn't going to be generally sought out for some splashy headlines. I wouldn't be shocked if nothing breaks on casting before filming begins honestly, if all the Comanche actors are generally unknowns.
But the good news is, we've been learning bits of info since our report that is confirming Skulls appears to be still moving along and on track, with filming to commence this year.