That could be true. That could also be a coincidence,
Highly likely unlikely to be a coincidence
Of all the words that they could possibly have chosen for a Fighter / Warrior Guild I'd wager that not a single one of us would have suggested the term 'Companion' as an obvious or likely choice. Then we discover that there is a lore background to the term in Nordic history.
No, definitely no coincidence in my view
Hopefully there'll be plenty of lore background, with books, notes, quests to find ancient artefacts etc