Unless you believe in an afterlife, you technically gave him the peace of mind that his plan would work. He probably died a bit anxious, but that's not too bad. Better he knows how ill he compares.
I like to find his logs and then throw his own words back at him and demonstrate that he learned absolutely
nothing on his journeys.
"All the roads you walked lead you back here, to repeat the same mistakes of the past you accuse me of."
that's the point
people take caesar's legion supposed to be rome too seriously
caesar himself says it's little more than a roving band of raiders in its current state
Yep. Caesar knows damn well that he's only Caesar by name, and he's hoping that by crossing the Colorado and taking New Vegas he can have his Rome and be Caesar.
The costly war in the Mojave over the Hoover Dam would fracture the Legion into smaller nations, like that of Alexander the Great. My credentials as a historian are sparse, but interestingly, there is a historical coincidence between real-life lore and New Vegas lore.
Counterargument: Rome following Caesar's assassination which lead to an immediate competition among his immediate successors to fill the power vacuum, a rebellion by the Senate, and after less than a decade of relative stability under the Second Triumvirate Rome the expulsion of Lepidus from it and Rome getting split into two between Antony and Octavian, with those two cementing power in their respective areas of control before having it out for the whole big thing.
If the Legion wins, then Caesar is probably still alive thanks to the Courier since him winding up dead in the surgery either by accident or not will force you out of the Legion questline unless you persuade Lucius you didn't cock it up on purpose, and the Courier is almost certainly his appointed successor given the minted coin in your honor following the conquest.
If the Legion doesn't win, Caesar is either dead by the Courier's hand or shortly afterwards to his tumor, and someone needs to get the blame for the second defeat, and its most likely going to be Caesar if Lanius is alive (since Lucius and Vulpes aren't dumb enough to blame a still-breathing Lanius, and Caesar is the only common thread between the first and second defeats) or Lanius if the Courier killed him at the end. Either way, you're looking at a showdown between Lucius and Vulpes at minimum and a possible three-way between Lucius, Lanius, and Vulpes.
Unless of course the Courier commenced TLD on Fortification Hill in which case its going to be a total free-for-all over Arizona that will probably resemble the breakup of Yugoslavia more than it would the Diadochi Wars as a result of the Legion's tribal nature and scorched earth approach to campaigning. Despite Caesar's claims to the contrary many Legionaries still hold their older tribal loyalties. Canyon Runner at Cottonwood Cove boasts of having Blackfoot blood, and despite having what is almost certainly a new name Antony is very much a Hangdog still and hates and resents the Legion for what it did to his tribe's beloved creatures. Those two can't be the only ones holding on.