It looks like the word arbeitsjubiläum has been spelled without the umlaut over the a of jubiläum. Technically this is wrong however I have seen this spelled in such a manner before. The engraving looks like a period font to me. See below for another example of the wrong spelling.
What a waste! It is such a beautiful bird. I would still keep it and hopefully the seller will give you a percentage refund that you are happy with. It still very nice, just no longer perfect!
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