I got substantial number of Ragnarok legendaries from other sources, than bosses. Like chests standing on the fringe of Lower and Higher ashes maps.
(https://i.postimg.cc/63Y5pRyk/Tqmap-lower-ashlands1.png)
(https://i.postimg.cc/rFdFqDcH/Tqmap-upper-ashlands2.png)
Fun fact: you can open Loki's chest before you kill him. Just run past him, open it and take what you need. You won't be able to open the door though and progress the main storyline until you fight him.
Sometimes nothing happens when we click on the 2nd orb.
you might've missed on some loot.. the 2nd orb will open if you stand at the very edge closest to the orb before you click on the orb
https://m.youtube.com/watch?v=FXv3fA8zXtw
just skip to the end when surtr is dead