Well, I'm going to state the opinion noone else wants to mention. At 75 years old it doesn't mean she's totally passive or doesn't have an agenda. You'd be surprised at what a lot of seniors get up to, and how a lot of them don't hesitate to play the "I'm old, it was an accident" card.
While it's possible this was an accident, a cable that is that signifigant, above and beyond that being a bad design choice, being accidently severed by someone seems to be beyond belief. While possible that it was an accident, I wouldn't dismiss the possibility that she knew what she was doing, or someone else put her up to it.
Either that or the story is a total fabrication to cover the goverment taking down that internet for a period of time for whatever reason. I believe the term disinformation started with the USSR, and this is it's old stomping grounds, despite Georgia's interesting recent relations with Russia... they probably still routinely operate in pretty much the same ways.
The disturbing thing to point out here is that this shows the viability of an "internet kill switch" at least in this neck of the woods... which might be why everything was so dependant on that one cable. This could be a test of that.
While potentially real, I mean wierd stuff does happen, this one strikes me as being a bit beyond belief.