So I was in for a challenge and was soloing lv3 fractals on my warrior for the hell of it when I ended up on the colossus fractal. I was fighting that first boss with the hammer for a while when i messed up and went down. I decided that maybe i should go for another fractal and used Vengeance to get back up and used the button to return to the hub. I died in the hub and got the option to respawn at the start of the fractal checkpoint. I did so out of curiosity, and the hammer guy was gone and his hammer ready to be picked up, had fun with the rest of the fractal. Also, if you return to the fractal in this manner the button to return to the hub is switched for the one to return to Lion’s Arch.