It seems all of the mentions of kegs exploding all go back to that one 2007 big brew incident. I remembered seeing threads about that years ago is why I knew to check (whew!). But it seems like even they had boiled in that keg for a while before the incident, and others that had checked because of it and had no holes had been ok. I just ran out of time and didn't want to deal with cleanup of slivers all over the place if I didn't have to.
We did brew on Sunday with it and didn't die, so that's a plus.