The last set of photos seem to show a lot of rust on the fracture surface of the barrel. Also, there seems to be a shiny portion and a dull portion to that fracture surface. Almost looks like there was a pre-existing crack in the barrel, which finally weakened enough to catastrophically let go the rest of the way.
Also, with no injuries and an $800 gun at stake, only someone with lots of money to waste would hire an attorney. Plus, S&W ain't doing nothing without the gun in their hands. The OP's only realistic recourse is to send in the gun and hope for the best.