“Botan” is a pun (i.e. “botan nabe” is a Japanese dish made with boar meat) so it doesn’t have the same implications. “Button” can be an endearing pet name in either language, but the English usage doesn’t cause this level of contextual confusion. It might seem like an accurate translation on the surface, but it does the related dialogue a disservice. Furthermore, “localizing” puns usually makes them sound unnatural or not as clever, which has unintended side effects (DAD JOKES). Sometimes a localized pun will make even less sense, depending on where the reader is from (English has many dialects too).
That’s probably why it was an easy decision for the team. This Dangopedia is a great solution to the problem many translation teams run into. Unfortunately, nuance is often lost in translation unless you educate the reader beforehand. Shoving “translation notes” into dialogue boxes can feel intrusive towards those who are familiar with certain customs, while very few people will read the notes if they’re kept in a separate text file. The Dangopedia integrates these notes into the program so it’s unobtrusive, but still very easy to access - which is a great middle ground!
But anyway I just can’t wait for the day when Anime dominates America and becomes another cultural phenomenon we adopt into our country!!! 
