Gotten a total of 4 hawkmoon to date. My first ever exotic when I started this game was a hawkmoon. I'm a day 1 player and like a long time ago when I first went into the VOG I got to the exotic chest and my first exotic showed up. Next VOG I got a hawkmoon from atheon. The next 2 was after dark below came out and one was from a nightfall a while back and just this week I got a hawkmoon from a legendary engram. I've seen drops from atheon and the first chest after the Templar in vog far more than anywhere else. But that's my experience. A friend of mine got it at atheon as well.