Heart pendant found but not in inventory

[Guarmanda]

I've done the hole without even checking what I was winning, I just took all chests and went out.
Later in the game, I looked at the wiki about how to defeat developper and I read that I should have had this item in the hole.
I went back to the hole, all chests were arleady looted, but no heart pendant :/ seems like I'll have to use my chocolate bars...

EDIT: edited game save manually to get the item

[Mekomancer]

you have to kill the lost tribe warrior to get it, not open a chest