If the answer is "victory" then how can McCarthy survive?
I think you're 100% right, the Chaos Caucus wants McCarthy's scalp. They (and their supporters) believe that cruelty is the proof of power, humiliation the proof of dominance, and they want it to be *absolutely clear* that they hold the whip hand.
The wild card imho is: are there 4 Rs in purple districts who can see themselves succeeding as Independents or even Dems? If 4 of them switch together, *they* hold the whip hand.
"In a parliamentary system, the insurgents would be in their own party, and there would be coalition negotiations"
Certainly not in England or Canada with a first past the post system. They would all be Conservstives just like they are all Republicans here.