Yeh, it is not necessarily just Trump vs. Cheney. What happens sometimes/often is that the obnoxious attacker is not electable but ends out doing damage to the other party so that they end out voting for neither the attacker nor the one being attacked and go with someone else. That is scenario where DeSantis benefits.
Some pundits think that an example of this is Clinton's campaign when he was opposed by H.W. Bush and Ross Perot. They argue that while Perot himself was never seriously electable that he did such serious and continuous damage to H.W. that more people ended out voting for Clinton. Perot did actually get some votes that mucked up things too but the pundits argue that the bigger impact he had was in devastating Bush.
Anyway. lots of scenarions. Nothing looking good for Liz herself though. Just a chance to jump in front of parade going by and declaring herself the leader.
I don't think, at this point, any more damage can be done to Trump that what has already been done or said, or what the man has done to himself. The people who support him right now, at this very minute, will do so no matter what else happens. The people that do not, will never.