All kanen alphas can only be included once in the same BG, but they dont have the unique ability. I dont know if they are supposed to be unique or not, but whichever is the case, I think they should either get the ability or we should be able to put them twice in a BG. Hope this helps
Unique has been removed as an ability. Champions who are supposed to be it instead have a limit of 1 in BGs.