I agree with Kelly. I think your OBS had a valid point, and was probably a bit upset that some other Doctor jumped in. I agree with your OBS he probably has seen this too many times and all turned out to be fine. IMO i think it best for your body to go into labour, this way it does prepare the baby for the birth, then take it from there, if you then need a cesar it will be done but atleast you have given yourself the chance the to have a natural birth (if thats what you want).
I am not that tall (166cm) and am a size 8 and had no problem pushing out my 2 boys, also another girlfirend diagnosed with CPD gave birth with no problems, so they can get it wrong.

Goodluck but it looks like your going to give birth very soon.