Uh no; I disagree completely, if they weren't between a mother and baby this wouldn't have been an issue;  she false charged to tell the woman to "take off"...

I've encountered plenty of bears in Alaska, a couple times encountered Cubs only once had the misfortune of being near a cub when it's mother was near.  She made angry gruff noises, and did a false charge and we beat feet and got the hell outta there... We didn't dilly dally and wonder if she meant what she suggested.  That woman should of been calling for the male guide with the bear spray and heading in his direction. 

This situation didn't require a gun as much as it required humans with common sense.  A gun won't deter a mom whose worried about her baby.