I'm so glad that you've switched vets because if my vet had said that you should just leave kittens to die I would run from that vet as fast as I could.
My future kitten Starr is a bottle fed baby and was rescued at 1-2 days old. He's the sweetest little kitten and loves people. His foster mom deals with many many bottle fed babies and they're always so sweet that they never have any problems finding homes. Two of her cats were bottle fed by her and they are sweethearts. I think that this vet should visit some of these foster moms who have bottle fed babies and then I think he'd change his mind.