Is my Grandfather Seamaster a patchwork?

Syrte

Hi. Am late to this thread - what happened in the end?

The reason this case should not be polished is because it appears to be a gold plated case where some of the gold plate is already peeling off (see the back of your lug).

Strange that a supposedly authorized watchmaker refuse to repair a broken watch part, rhat’s what a service is for, maybe they’re not authorized after all and can’t get parts.

Syrte

Okay, my bad, you’re right, I had not seen the picture showing the inside of your case back.
in any event, like others I would strongly discourage you from polishing the case: you’re dial’s redone, but the case is pretty nice and nicely defined and there’s a big risk that getting it polished by an unknown watchmaker would ruin the shape of your case.
Why take the risk to destroy the best part of the watch?

Well; it’s yours anyhow, but it would be a pity.