So after searching on WoWhead and other information sites. I couldn’t find any uptodate information on all the possible items you can get from fish pools/treasure pools.
But, I just got the epic cosmetic shield called [Fallen Dalaran Defender] from one of the treasure pools in Hallowfall. Which I thought I could only get from Captain Oathmyts vendor in Hallowfall.
That being said it seems like you can get some if not all the vendor items from treasure pools. I’m sure its very rare, but seems like a possibility.
[Fishing/Perception skill]
300 (Default fishing skill level)
+18 Fishing Skill (Aqirite Fisherfriend fishing pole)
+59/100 Fishing Skill (Algari Anglerthread)
+30 Fishing Skill (Ghoulfish Delight)
+329 Perception (Aqirite Fisherfriend fishing pole)
+42/100 Perception (Algari Seekerthread)
+150 Perception (Ghoulfish Delight)
For a total of 407 fishing skill and 521 perception (not using any other buffs/gear). With that, thats the results I got from obtaining said vendor item from fishing.
Now I’m wondering if I can obtain more items from Captain Oathmyts vendor through just fishing, and is it very rare? Only time will tell, seeing as no website has any uptodate information on all possible item drops from fishing pools/treasure pools.