Héctor's exactly right in that assumption: Peter's blight was there long before he died, and thus has nothing to do with the spell resurrecting him. There might be complications in trying to restore him that might affect his powers? But nothing actively draining away.

He realizes too late he's said kind of a dumb thing and winces a bit. "You really, really miss her," he says, not surprised but still awed. "She has to be missing you too."

Does that help? He hopes it helps. It certainly helps him knowing what sort of relationship Héctor is picturing.