WHM healing DRK question

Nobody died, so I guess I did it right, but I thought I’d ask because I wasn’t quite sure.

The dark Knight was about to die, so I hit benediction. Just my luck, right after that he hit living dead.

I poured everything else I had into him, tetra, lilies, regen, I think I might even have popped off a couple of cure 2s.

He did not die. Did I do it right? Or did I do unnecessary extra healing?