Renown potion locations and quests

[gisborne]

So it's pretty common knowledge that you can do a quest in KaK for 3 renown potions. I saw a post on Reddit that gave the location of a potion in Blighted Isle, at 31k, 46k in a pile of dirt on an island. In chat someone told me about another potion at 23k, 0k in Ostland in a bottle next to a tree on a hill in the RvR area. I did a quick search online and didn't find anything about these or other locations. If you do know one, would you post it here?