Grizzly Bear vs. Nikon D4 and 600mm lens

I recently rented a D4, Wimberly head, and 600VR from you, and the day
before yesterday, I had a little bit of an accident. I was photographing a
coyote here in Yellowstone and I followed it into the woods about 300yds
away from the road. As I am taking pictures of the coyote, I heard twigs
breaking behind me, and as I turned around I saw it was a grizzly bear. I
picked up the tripod with the D4 and 600 on it and slowly started to back
away. The bear got closer and closer as I tried to back up. When the bear
got to within 20 yds. of me, I bumped into a brush pile that I could not
lift the tripod over, so I had no choice but to leave the gear and continue
away from the bear.
And here’s what happened next…