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If I understand this correctly, the situation is that Obelix says that he doesn't want to buy a chariot, but someone saw it in his future after reading his palm. "Apparently it says here that I should" is a good idiomatic way of expressing that in English. It's not a close translation of the German, though.
If the German and English translations were made independently, from a French original, that could explain the difference in the phrasing.