SPOILER Cryptic Key

Hey guys,
A few minutes ago my guild and I were warring around the Silent Expanse, and the ruined city in particular. We found a rare mob called Ancient Construct. When we killed it, it dropped this item. The Wynnic text on it translated to the following:
"Opens up my caches. Don't touch!! - Arna"

I searched the forums for any references to this, and couldn't find any. I searched in discord and found one dating back to the 12th of January, during hero beta. On the wiki, there is a mention of the Ancient Construct on the rare mobs page, but this doesn't provide much info.

Anyone know what this is about, or anything about this Arna character? Is this new? Any ideas?

Credit to tomjerry92 for initial translation and WamWamBoyooo for cross checking.

EDIT: The key can be used to open a door at 709 -464 but I'm still interested to see if we know anything more

 

theres a little gazebo thing with a keyhole in the floor in the olmic city, right click on it with the key and it opens the floor a bit to reveal a chest. the gazebo is at 709, 93, -464

 

is there only one location? It sounds like the item is implying there's more

 

Just found it, ty. Would still like to see if the community knows anything of Arna

 

I know of 5 of them, but there might be more.

 

Ah, okay. Guess it's hunting time
Would be cool if we could compile known locations in this/another thread