I agree with this assessment wholeheartedly, given where we stand with details at the moment.
Her father, so far, sounds very similar to my own. Maybe he doesn't drink often but in this one scenario alone, too much happened to make it seem like a one off problem. He gets so drunk he can't drive. Didn't plan ahead, so he calls his daughter, who doesn't apparently live there and will be leaving soon (what a way to spend time together). She shows up, but since he's the dad, he doesn't owe her anything, he doesn't have to rush out to meet her, he can stick around as long as he wants. Even more than that, he bought the car she's driving, so she can sit there until he feels damn well and ready. That's a very narcissistic way to behave, to value your own kid's time so little because you're the parent, worthy of silent respect.
She has had enough, curses at him. He flips. This incident didn't just happen and end, he cut his night short to get a taxi and follow her back to continue the fight. That's some serious rage, to follow through with that level of aggressiveness.
He immediately proceeds to demand the car back, which is essentially him holding money over her head. "If you aren't going to put up with my shit with your mouth shut, I'll punish you." She refuses, he gets violent. Who knows how far it would have escalated if the bf hadn't shown up?
And in that manner, he's an annoyance, he disturbs the flow of things. He's not willing to eat shit. He'll defend her. People like her dad don't like that. It means he can't get away with bullying her and making unreasonable demands without someone there to stop him anymore.
I came to the same tipping point with my parents last year. Mine have been pulling similar power plays with me for a long time but I've been working to separate everything from them and have successfully done so. This drives them nuts. Last year, they tried to bully me into planning every single aspect of my wedding around them and their needs, to the exclusion of over half of my husband's family. It was nuts. I finally broke down in tears after a phone call and told my husband that I didn't want them to come anymore, I wanted to uninvite them. So he grabbed up my phone, called them back, and left a message telling them they were no longer welcome. Oh they were so mad, no one had ever gotten directly in their way of bullying me, and for a while, they definitely were not keen on him anymore. But I totally put a ring on it. xD
The way this family came together to bully her into dumping this guy really says to me that this isn't the first time he's acted out this way. I would think that if this were truly a one off, someone would be a little more horrified, not so goddamn relaxed and pointedly mad at the one person who had initially shown up to mediate.