Much of my family is in the medical field, and I can tell you that the concerns with VBAC ARE REAL. IT is simply not worth the risk, thus the reason that the majority of doctors won't perform it, the majority of hospitals won't allow a doctor to perform it under their roof. If on top of that there are other concerns (like it seems there are), c-section is absolutely the safest route to go. Repeat sections are always easier... do not be afraid. We all want vaginal, perfectly romantic births-- but that isn't reality. Listen to your DOCS-- they are smart, informed, and they know best. You have mulitple opinions-- most docs and nurses will tell you stay away from VBAC-- esp. if there are any other concerns with the pregnancy.
I can tell you that i've had 2 sections, my hubby is a nurse, and would not even allow me to think or contemplate a VBAC-- he feels that strongly. That should tell you something.
You'll be fine. Listen to the doc!
PS: My neighbor had a vaginal with a large baby, experienced shoulder dys, and the child has been in therapy since... she is now 9 and still doesn't have full use of her arm. It was scary for her, and she happily had the section the second time.
PPS; being cut open isn't as bad as what can go wrong with a VBAC, esp. with a large baby-- ruptured uterus?? BAD.
PPPS: I am so scared irrationally of another section that even though I want more kids, i've put it off and put it off. You are lucky that the decision is made for you. I let my fears get the best of me. I can sit here and tell you "it is okay", but I can't listen to myself. The irony! Don't give into the fear. Safety first!