
There doesn't have to be a scan. All my bitches that have needed sections, have gone straight in for surgery. I can always tell if something is not quite right, and with inertia I don't see the point in waiting around. Over the years I have learned to recognise inertia pretty early on.
If I think it is malpresentation I ask for an x-ray or scan, and won't let them jump in with oxytocin until I know what we're dealing with. I feel that I am paying for it, so expect to be involved in decision making, but, to be fair I feel that there are times that we know better than the vet when it comes to knowing our own girls. Like the vet who told me that my bitch had finished - she was a first time whelper and had inertia. Oxytocin produced pups , she needed 2 jabs - the most they should give. I insisted there was a pup left. The vet told me that I was wrong, it was the spleen. I argued and insisted on a scan. As soon as I pointed out the heartbeat, he agreed to move fast!
But even with an inexperienced breeder - who lets the vet decide what to do, they should expect a vet to produced as many live pups as possible - which they insist on at the hospital I use. I have only ever had a dead puppy when we actually knew that it was jammed and caught in the ribs, and it needed removing. The rest of litter had been delivered naturally, and we knew the pup that was caught had already died.
It is up to the surgeon to ensure all pups are found, and to check everywhere. My own vet was taken a bitch that had just been brought into this country, after having a C-section. She was very, very poorly. He was extemely cross. He found a decomposing pup in the vaginal canal, and told me that if it had been a vet in this country, he would have personally have taken action to have the vet struck off. So yes, visual and feel around. I have never had to deal with anything as awful as the OP. I would be heartbroken if this had happened to me. And, by making an effort to get a vet struck off, means he can't do this again to another person.