If Dane turns out not to be Constantine's clone, I'm cool with him being half-angel.
But I'm not against him being Constantine 's clone that was raised by Nightmare Nurse. The last part is on his wiki page. She popped up in Swamp Thing as a member of the Suicide Squad. Maybe that's how Dane gets noticed by the Titans? There's a setup for a good story.
John Constantine is one of my favorite DC characters so I'm cool with Dane being his clone. Maybe they should've used Dane in the Mystery of the Meanest Teacher OGN?
Just a thought.