Dulinor is a BELIEVER, a zealot. He genuinely thought he could pull it off.
And then he
failed.
Dulinor was that zealot right up until the instant he botched the murder he'd planned for so very long. Instead of neatly killing Strephon and everyone throwing roses in the air, Dulinor had to shoot Iolanthe, Iphigenia, and the Aslan ambassador too.
He had to watch the four bodies fall, had to hear all the screams, had to see the splatters of blood and brains, had to watch the four new corpses twitch, and had to smell their bowels and bladders empty.
There were no flowers, no neat bullet holes with a single teardrop of blood, no hosannas, no hymns, no heartfelt thanks. Nothing that he had dreamed of for so long happened. Nothing happened but reality and reality is something no zealot every likes being introduced to.
Then all the other bad news came crashing in. Only one Prince was killed, the rest of the Guard didn't meekly surrender, the Moot was in chaos, the Fleet undecided, and no one was handing him the Imperium on an iridium platter like they were supposed to do.
Dulinor the Zealot met
reality in the Throne Room that day and, when Dulinor the Uncertain fled, reality won hands down. Strephon, Iolanthe, Iphigenia, and the ambassador weren't the only ones who died. Strephon the Zealot died too.
There is no way he'd surrender.
He surrendered to a
piece of farm machinery, Wil, because Dulinor the Zealot surrendered when the events of 132-1116 crammed a big hot steaming
Reality Sandwich down his gullet.
He'd never surrender. Not even to save his loved ones, because he genuinely believes his own hype, as savior of the Imperium.
He'd surrender when faced with evidence of his own treason, just like he surrendered in the Throne Room after his plans didn't unfold perfectly.
A sane man would not have started the civil war.
That's true. I'll point out, however, that there is a fine line between zealot and
martyr. When the zealot can no longer deny reality, all too often the martyr steps in and takes control.
Dulinor most likely knelt to take a 9mm in the back of the head with the words of Sydney Carton on his lips.
The assassination, like Virus, falls apart under examination because it's just a device to bend the setting in a certain direction.
In the end, that's the
real answer.