Yep, it slightly damaged the other cylinder on the same headside as well..... it even threw a piece of the valve to the other side of the engine via the intake into another cylinder...
That's what happens...it shares through the intake manifold. If it were a hyperutectic piston failure it would have sent crumbs everywhere.
Remember that little sheet of paper that came in each one of those boxes warning you of potential of seat failure/dropping out due to the amount of material the cnc removes below the seat to make a bowl out of those buckets.