Disagreed on the second.
Without elaborating much on it, any bully who bullies his into getting what he wants could become a alpha. However if the bully is a bully and if there is anyone with a spine in the group or if the group is mature the bully would lose his alpha status and become openly disgusted or ignored. If the bully os tactful the group has to be mature see through him lest he'd use tact and charm to disarm people's defences.
I've seen this happen a plenty of times. Bullies fetting away with shit, people eventually waking up or someone with a spine standing up to the bully directly and indirectly.