Re: Would you try for another VBAC if...
I would explore checking in with a therapist that specializes in PTSD and PPD and cognative behavioral therapies. I had a lot of issues coming to terms with my birth (and it wasn't as tramatic as what you've experienced). At best, it may help heal the trauma of your prior experiences and it may help you make the right decision for you on this next birth.
I did something with my therapist called EMDR which is a method of dealing with PTSD. It involves describing the traumatic experience while listening to a sound that bounces back and forth (bilateral stimulation). It sounds goofy and weird but it's been an accepted therapy for PTSD for the past 20 years. It helps your brain learn to process traumatic experiences.
It made a trememdous difference for me in one session. I am now pregnant with second kiddo and I have worries about how this birth will be. But I don't feel like I am dwelling on what happened in the past. I think if I hadn't resolved my trauma from the first birth, I would be in a far different place.