I'm sorry, but I disagree. I saw in medal factories they could chage the original die, and in TR they had the tools to make it. Removing small parts of metal was not hard then and not now, and the big flaw you are referring to is really big; but is big for us, I bet not for them. Again you are focusing in something that is totally useless and IMO it is only our problem, not their.
About the rest: prepare a die in steel (now silicone molds are the most used), put melt silver on it and all is done. No need to complicate what is simple. Ring could have been done flat or round, I tried both and results can be really close between them. Same time as prepare a steel die for die struck. But we don't focus our attention on flaws, dies, etc etc.
About the question why they were cast is useless to make it, since they could have had tens reasons to do it. We'll never know. Maybe Himmler himself ordered them made that way, Who knows? These are only speculations.
At the moment I haven't any decent one to make some shots, but I'll do with a Krimshield, that is die struck.
