My friend and I were collecting the worms (8 black ones and 8 blue ones) in the Nether for both triumphs and in the end, we noticed we were missing 1 worm. My friend was 1 short for the Resolute Collection triumph (black) and I was 1 short for the Ambitious Collector triumph (blue one). We were like "no way" so we visited all 16 spots again and there were no worms missing, so I guess the triumph tracker is bugged or something. Hope Bungie can acknowledge this issue.