I fought for, and got, a CS for my twins. I then fought for, and got, a CS for my third (singleton) baby.
In my case, the consultant pushed for me to try for a vaginal delivery because baby 1 (the baby nearest the cervix) was head-down, despite baby 2 being breach. He said baby 2 would probably turn during labour with baby 1, and that failing that they would use external manipulation to turn her. Failing that, they'd use internal manipulation to turn her, and failing that, they'd deliver her breach (which would be easy because baby 1 would have stretched everything already).
My first and final thoughts were Fuck. That. No. Way.
I researched thoroughly and presented my case to the consultant. I talked about the risks of vaginal birth and CS. I talked about the risks of vaginal birth and CS with twins. I quoted NICE. He was pretty blasé about all of my reasons and said I should try vaginally and go for an emergency CS if it became necessary. At that point I cried. He scarpered and sent the midwife in to see me, and 10 minutes later I was outside with 'plan for a CS' written in my notes.
With my third baby, I asked for a CS from the start, but engaged with the midwives and discussed VBAC. I went to the VBAC session with a senior midwife and planned what I would want if I decided to try and labour. I asked for a new consultant when the first said he wouldn't do a CS. I agreed to book the CS for 40+2 (they were hoping I'd go in to labour and decide to give it a shot). I turned up at 7am on my planned section day and the midwife breezily said "so, we're going to try a sweep first?". No. Fuck That. I informed her I had turned up for my planned section, on the day that my planned section was booked for, and I did not want a sweep, thank you very much. I was taken to theatre and had a CS.
So, you're friend needs to step herself for a battle of wills. She may need to change consultant/midwife. She will almost certainly need to research, plan, and argue her case. She may need to cry (which isn't too hard once you're past 28 weeks with twins TBH). But they should agree to a CS, and once it's on her notes, she should be ready to fight for it all over again if she labours before the planned date. They should move straight to an emergency CS is she had been planning a planned CS, but they will more than likely suggest just seeing how this go ...
Good luck! And wish her well on the amazing twin mum journey :) I am almost envious of her just starting out with twin babies
Almost ....