It's for the best. It's true to Louis' nature, to punish Lestat far more cruelly than the fire would have.

Because Lestat has been punished. Louis saw it.

(It does not occur to Louis, not really, that he has punished himself too.)

"I believed he saved me. Believed it for a long time."

It had all come together in Louis' mind. When he had recited it to Daniel, Louis had seen it in his mind's eye: Armand, exertion written all across his face.

Lestat's fingertip remains, holds Louis in the moment. No perilous slip backwards into that memory, onto that stage.

"I know it was you now."

And he knows it wasn't without great cost.