@kebb bibles were translated much earlier than the sixteenth century (with the rise of protestantism) but they generally were not complete translations, and as they were hand written and not mass produced before the printing press there is no registry of (most of) those translations. Another possiblity here is that they are not speaking danish, but english, since the the vinking spent a long time invading england it would'nt be so strange if some of them learned the language and even stole a bible.
This or the author didn't really think this through 😅