I like this theory but I doubt Taft the Grimoire card writers really thought that much about it and if they did you could simply say that the Books of Sorrow were translated to English and that 10 Earth years simply equated to the amount of time stated in the original text.
But still good theory and I like the comparison to our own solar system as a reference
English
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Consider this: Whoever translated the Books to English would have had to know how long a hive year is to translate it into human years. I just don't see how that possible, so I think that whoever translated the Books just knew how to translate the word "ten", but doesn't actually know how long that is in human years