It's called Mystery Shack.
Here is the link: https://steamcommunity.com/sharedfiles/ ... =580300902
There is also a ladder to the rooftop in one of the rooms. It's the only way to access the terrace on top, the Mystery Shack sign and the large wooden pole.
There is a chest on the roof terrace with grenades inside, so you have to either remove it or find a way to disable weapons. As far as I explored there are no more weapons on the map, unless there are secret stashes somewhere else that I couldn't find.
I hope it gets added.