I thought I figured out the ending... I was wrong! (spoilers)
I thought it was some kind of setup, kind of like the movie Game where the clients of the tour company get tricked into believed it's all real, but in reality it's all actors playing in a carefully designed set. Especially when Yuri so fire ashes and tried to cover it up so as not to ruin the game. And then none of the attack scenes were really shown and I thought one of the dudes was playing along and that the hairy guy and his gf were actors... and all those blood and guts were fake.
I expected them to walk into some kind of audience clapping or something...Damn...
Definitely will rewatch...