Sorry, it's completely RNG, those triumphs don't actually matter, I got the sword on my second run, teammate got it on his first, I proceeded to get two more swords over 30 plus runs. It took my last teammate about 35 runs to get his and he has all the triumphs except for solo flawless. It's just how Bungie has their game; everything is RNG to pad play time, you'll have to decide if wasting your time is worth it or not. The sword itself is junk.