I'll keep this short. Ewing could have easily just shot Frank and Ella before he burned the house down. Instead, just a gentle little love-tap to Frank's head and lock him in the closet with Ella. Now really!
Mountain Man
I'll keep it short too MountainMan.
Besides eliminating them, he wanted to frame them for the bank guy's murder (whose tortured body was strung up in Ellie's closet) too, so he's not going to start shooting them. Better they perish "tragically" in the fire, after they'd "murdered" the bank guy.🐭