I'm curious about what your problem is in fixing the high elbow. I noticed I had a high elbow one time, and all it took to fix it was being aware of it. In other words, I was able to position my elbow either high or low just by deciding where I wanted it, without having to worry about back tension, etc. I recently exchanged posts with someone on this forum and found that different people get to full draw in different ways. My elbow starts low and rises up to the full draw position, where his apparently starts high and drops down to the full draw position. Maybe that's why I didn't have a problem correcting it? I don't know, just a guess.
I was told by Fred Asbell in a traditional shooting clinic to use my elbow as an indication of back tension, not by how high or low it was but by how far back it was. If my elbow was still kind of sticking out to the side, then I didn't have good back tension, whereas if my elbow was pulled back such that my forearm was in line with the arrow, then I had good back tension.
I think you need to focus on both pushing with your bow arm and getting good back tension on each shot. I think once you achieve good form, those two things are about all you need to focus on, other than the target, of course. Some would say you need to focus on your release too, but in my experience, a good or bad release is a symptom of other things that are going well or poorly, not a cause.