Im stuck in the Phaaryl Megalith- Boss is bugged and so is the instance

I went through 10 or so bosses on The Phaaryl Megalith and now the last boss is bugged. Its stuck in the middle of the map, I cant do damage to it and it cant do damage to me. Ive tried exiting game but it just brings me right back in the same instance. It wont let me teleport to my hideout either because its a boss fight. I am unable to play the game

Please help

Bug report- 3,766,640,502