while i dont entirely trust her, i will say that "Ambition" is an extremely vague term in this context. Ars assumes that ambition is strictly political ambition, ie they want a lot, ,while it could be that they are willing to do a lot to get what they want. He assumes she wants a lot...
The way they treat his Blessing is more along the lines of (atleast to my understanding) "I want to follow Almus" rather than "I have to follow him because he was named Commander". The guards whispering rumors questioning if he is all that special or not kind if lend it so that he's not...