I don't think that's a factor that comes in to play in this surgery ... it doesn't matter if another doctor hasn't seen your legs before, they're using the x-ray machine during the surgery so they see where their tool is going and where the nail is at all times, they're not guessing.
Maybe "guessing" is not the best term for what I meant. But every patient is unique, sometimes the doctor had to ream a little bit more in one leg, maybe had to put the screw a little bit different in one of the legs, maybe there was some nerve problem during the first surgery in one leg, etc...
Your original surgeon would know about that. If you go with another one he would have to discover this by your medical records, x-ray, etc...
Anyway, I don't think 4k is such a big difference in price considering the cost of the surgery.
But you're right that that's a much simpler procedure, maybe it won't make any difference.
My opinion it's only what I would do (and what I did - I went back to Germany to take the nail out with Betz).