nice story!
What he should have done was extended the tripod and held it up to look big - grizzlies don't have great sight, you're supposed to back up slowly but if the bear continues, make yourself big, stop and speak loudly in a calm voice, avoiding eye contact.
At least thats what I was taught in canada - luckily for me I saw 5 grizzlies in my time there, but none of them were 30 feet away walking towards me. I'm sure i'd have just legged it!