That’s some nice piece of research you did along with elbala, that was a good read.
Honestly, I’m not sure if there is a mystery here. In my opinion, the note may belong to one of Yakchal’s followers mentioned here: https://tibia.fandom.com/wiki/The_Frostspire%27s_Secret_III_(Book)
They were sent to find shards for her master, who later used big amounts of shards for his rituals and experiments.
Strange things moving and glitter behind the ice were probably quara scouts. They didn’t kill him after all. Looks like he died because of hunger and cold. That’s why he dreamed about warmth.
I checked the place you marked on the map – undergrounds of Chyllfroest. There are 2 ghastly dragons in that exact place, and single undead dragon 1 lvl below:
Ice and rocks + it’s a bit far from the quara cave.
Nevertheless, I wish there would be a secret passage or a cave with the body or something similar…
Thank you for this post. 🙂